T.R | Title | User | Personal Name | Date | Lines |
---|
1374.1 | ooops! | AKRON::RATASKI | Veni, Vidi, Vomui | Wed Oct 23 1991 10:39 | 8 |
|
Dave - I tried to copy the predator manual and got the following:
FTSV Job 1809 (FTSV_1809) finished at 09:34:18
COPY UPSENG::SPITFIRE:[WALTER.PUBLIC]PREDATOR_MAN_*.PS DISK$USER3:[RATASKI]*.*
%RMS-E-PRV, insufficient privilege or file protection violation
-TomR-
|
1374.2 | My fault. The file is now copyable. | UPSENG::WALTER | | Wed Oct 23 1991 14:46 | 4 |
| Shoot, I did it again. I put the file in the [.public] directory
but forgot to open the protection. You can copy it now.
Dave
|
1374.3 | but how do we build them lighter than air? | ZENDIA::REITH | Jim Reith DTN 226-6102 - LTN2-1/F02 | Wed Oct 23 1991 15:20 | 8 |
| I saw a copy of the plans at lunch. Very nice job. Too bad the plane is
such a dog (I don't want my competitors to KNOW how good it really is
8^) I guess we'll all have to build them heavy with the stab hanging on
by a prayer? (This is how Dave describes the plane he won the CRRC HGL
contest with a couple of weekends ago)
Gee, with an arm exercise program over the winter, we can ALL fly like
Dave.
|
1374.4 | Planes, like people, gain weight with age. | UPSENG::WALTER | | Wed Oct 23 1991 22:47 | 5 |
| >> 8^) I guess we'll all have to build them heavy with the stab hanging on
>> by a prayer?
Ummmm, I didn't BUILD it that way. It just sort of... GOT that way.
|
1374.5 | Was that last title a cheap shot? 8^) | ZENDIA::REITH | Jim Reith DTN 226-6102 - LTN2-1/F02 | Thu Oct 24 1991 08:34 | 2 |
| But we want ours to perform as well so we have to build to what you've
evolved to.
|
1374.6 | I'm In | WMOIS::HIGGINS_G | The Moeman | Thu Oct 24 1991 12:07 | 11 |
|
This note couldn't have come at a better time. I've got all my wood.
Just got a new scroll saw, Lamar has my $5 "plan" dollars, and the
desire is there. It's just that damn World Series that keeps me from
starting ! And a bit of carbon fiber.....
This will be my first scratch built from plans so I would imagine that
things might be a bit slow. But with Lamar 5min away from my house and
this note, how can I can wrong ?? The resourses are here !!
George
|
1374.7 | I rate it a 9.5 | KAY::FISHER | If better is possible, good is not enough. | Thu Oct 24 1991 16:36 | 31 |
| Just in case somebody is wondering what the heck a Predator is...
Dave designed and has been flying this plane all summer. Every
contest he goes to he has a crowd around this plane and starts fielding
questions. Part off the cause is Dave has a heck of a good throw
and is a very good flyer. But after the awsome launch - what then.
This is a good HLG. Better than most. In the right hands almost
unbeatable. Dave routinely does a loop in hand launch. I've seen
Jim do the same with his predator.
It flys great, it's light, and it looks right. If it was glass and foam
and indestructible I might rate it as the best HLG available. But
given the constraint of built up wing and balsa fuselage technology
and the cost of $5.00 for plans...
I've got a workshop full of kits and plans and I need another project like
I need a hole in the head - but I just sent my $5.00 in for a set.
I'm afraid if I don't crank one out by spring I will be the only one
at the field without one. Kinda like showing up at the Gremlin
combat fun flys with a Aeromaster - yes the Aeromaster flys but
it ain't the same.
P.S. I don't benefit by the proceeds - just want to acknowledge what I
believe to be a real good deal on a real good set of plans.
Bye --+--
Kay R. Fisher |
---------------O---------------
################################################################################
|
1374.8 | | UPSENG::WALTER | | Thu Oct 24 1991 22:10 | 19 |
| Re: -.1
WOW, what great hype, Kay! Can I clip a few of those quotes and throw
them on the cover of the shipping box?
By the way, last week at the CRRC auction a member of the club brought
in his Predator (not for sale) which he had recently completed. He
added some personal touches to the design, like pull-pull rudder, a
built up hatch (rather than single block of balsa), and removable wing
tip panels. It felt a bit heavy to me for thermal flying, but he took
it down to Cape Cod the weekend before and flew with the Northeast
Sailplane nuts on the dunes. He said it flew very nicely on the slope
and was very fast (I'm not surprised). If anyone wants to know what
kind of lunacy goes on when the NSP guys show up, just read the new NSP
catalog. There's a page in there on their last expedition to the Cape,
and it had me rolling on the floor.
Dave
|
1374.9 | So how do we get zees plans? | ELMAGO::TTOMBAUGH | Homo Erectus with car keys | Fri Oct 25 1991 09:20 | 6 |
| I want a Predator. Would it be possible to post an address where we
poor souls who live west of the Conn. River, may send our money?
My wallet bulges and throbs in anticipation. Thank you.
Terry
|
1374.10 | Great little ship! | MICROW::PHILLIPS | DECtp Engineering TAY1-2 DTN 227-4314 | Fri Oct 25 1991 10:41 | 23 |
| I'd like to add my two cents about the Predator as well. I built 3 fuselages
and two wings for the Predator so far. My first predator fuse met an untimely
end in my workshop one day. It lost an argument with a 4x8 sheet of 3/4"
particle board. The second fuse is still flyable, but came out too tail heavy.
I had to add 3 ounces of lead in the nose to balance it out! It still flew
great at 23 ounces. Fuse #3 should be completed this weekend and I've been
keeping a close eye on the weight. I'm also building a new wing for this fuse
as well. My original wing weighed 9 ounces fully covered and used d tube
construction. It is one tough wing and has survived many wing tip cartwheels!
For the new wing, I plan to stick with what the plans call for(sheeted on top
from spar to LE.)
The best memory of flying the Predator is not of flying my own, but flying
Dave's ship in Acton one day. I think it was the second or third time out with
mine and I was having a little trouble getting it trimmed out properly. Dave
came to the field that day with his and helped sort mine out. After a flight
or two on mine, he says "Wanna try mine?" Sure, I liked to see how a well built
Predator handles. Dave offers to hand launch and gives me the TX. He launhes me right
into a thermal and I end up with a 5+ minute flight. It was great and the look
on Dave's faces was unforgetable!
-Lamar
|
1374.11 | preditor comments | RANGER::PITONIAK | | Fri Oct 25 1991 14:53 | 30 |
| Greetings,
I dont have the document with me but I think there
might be a couple of typo's in the instruction guide;
please correct me if i'm wrong.
1) Cap strip material is listed as wrong size, should be
1/16 x 3/16
2) material list only calls for one piece of balsa sheet
for the fuselage side...should be 2?
I also have a question on the instructions that I was hoping that
someone could help me with. Its the procedure for determining the
appropriate length to cut the inner wing upper spar to length;
the process which calls for the use of a ruler. I must be missing
something basic, but I am confused on how this works??
Any suggestions/elaborations would be appreciated.
Finally,
I have compiled a total material list which is very usefull when
purchasing the balsa/ply etc. It lists every part in total
qty. If anyone is interested let me know.
Looking forward to building very soon.
Mike
|
1374.12 | 2 pieces from one piece of stock | ZENDIA::REITH | Jim Reith DTN 226-6102 - LTN2-1/F02 | Fri Oct 25 1991 15:39 | 6 |
| You can get both fuselage sides out of a 3x36 piece of 3/32" balsa. I
think Dave was trying to specify the wood required for each major
subsection so we could build replacement units (a new fuselage takes
this, new wing takes this)
You did a nice job on the plans, Dave. I got mine at lunch. Thanks.
|
1374.13 | | WMOIS::HIGGINS_G | The Moeman | Fri Oct 25 1991 17:11 | 5 |
|
> You did a nice job on the plans, Dave. I got mine at lunch. Thanks.
Now if I can only find Lamar I'll have mine before the end of the
weekend.....
|
1374.14 | Don't worry, I'll find you... | MICROW::PHILLIPS | DECtp Engineering TAY1-2 DTN 227-4314 | Fri Oct 25 1991 17:34 | 13 |
| Plans? What plans?? I don't know nuthin' bout no plans, Ms. Scarlett!
:^) :^) ;^)
Don't worry George, I'll get them to you this weekend.
As a side note, it was an interesting lunch today down at Acton. Seems
a certain somebody, "scored a goal" with a certain borrowed "battered up"
Predator. Sorry, I couldn't resist ............ I'll leave the explanation
up to the others. ;^)
-Lamar
|
1374.15 | Send your money to: | HPSPWR::WALTER | | Fri Oct 25 1991 19:27 | 40 |
| I've got several issues to respond to in this note:
1. Address - Take your hard earned cash from your "throbbing" (?)
wallets and send to:
Dave Walter
425 Main St. #18A
Hudson, MA 01749
2. Regarding sending plans through the mail - Do people prefer getting
their plans folded up in an envelope, or rolled up in a tube? The tube
prevents the paper from getting creased but it costs more for materials
and shipping. Any preferences?
3. Regarding Mike Pitoniak's comments - Mr. Reith is correct, the one
sheet of balsa is sufficient for both fuse sides. As for the cap strip
typo, I fixed that already in the instruction plans (you got the early
version, Mike).
I seriously considered adding a diagram to clear up the description of
cutting inner panel top spar to proper length, but there wasn't time to
add it. Now I will. It's actually not anything critical, but an attempt
to maintain an accurate airfoil right through the polyhedral break. I
won't attempt to further explain it here, but hope to have new rev of
the instructions on the system next week.
4. Yep, guess who's Predator scored a touchdown today? Actually, I
understand it hit the post and dropped to the ground, the crowd sighing
in disappointment. I wouldn't know, I was attending a luncheon
commemorating the death of our old group. I entrusted my wings to
experienced pilot, Steve "Easy As She Goes" Smith. He's still shaking
his head, muttering "I can't figure out what went wrong..." At first I
thought he was pulling yet another gag on me (did I tell anyone what he
did to me last weekend?), but there was a very real break in the right
wing. It's actually not a big deal, no where near as bad as the time I
flew it between two sign posts that were about a meter apart. I'm sure
the stupid thing will fly again.
Dave
|
1374.16 | We were wondering where Steve found a cow bell to ring | ZENDIA::REITH | Jim Reith DTN 226-6102 - LTN2-1/F02 | Mon Oct 28 1991 07:30 | 8 |
| I'm sure it will fly better than ever.
Mike pointed out something to me that I didn't notice (who reads plans
anyway). The plans show the fuselage longerons cut at each bulkhead.
Personally, I put on full fuselage length longerons and notched the
bulkheads. I feel the one piece longerons add strength and it really
isn't a big deal to notch the bulkheads as you install them. We all
have out own personal preference and building style.
|
1374.17 | Longerons
| 18199::WALTER | | Mon Oct 28 1991 16:46 | 20 |
| Yeah, I wasn't real clear on how to do the longerons. My preference is to
leave an opening in the longerons for the formers, because it helps to
properly locate the former, and it braces the former in place.
Another item which may prompt some questions is the ply doublers on the fuse
sides. In the original design, I only used the doublers around the finger
hole area. But experience with my plane and Jim's suggested the doublers would
be useful right up to the noseblock. So, I drew it in that way on the plans.
It occured to me later that because of the ply, the formers will not contact
the fuse side between the longerons (there will be a 1/32 space). I suppose
that's not a big deal, but it may be a little confusing. One way around this
is to cut the ply into sections, allowing a space for the formers to meet the
balsa sides.
Just weighed my Predator this weekend. The glider which began its life at
about 14 ounces now tips the scale at 18 ounces. Boy, epoxy and plywood sure
are heavy. And it makes a HUGE difference in the way it flies, especially
noticeable from a handtoss.
Dave
|
1374.18 | Guess it's time to fess up
| SNAX::SMITH | I FEEL THE NEED | Tue Oct 29 1991 08:17 | 63 |
| Friday at the Acton field, I met up with Dave, Jim, Lemar, Kay, Pete, Dan
and about a half dozen other people. I think it was one of the biggest
turnouts to date.
I had hoped to have the Intimidator ready to go, but alas it was not. I brought
it for people to look at, but it was not ready to fly. Dave Walter, being the
gentleman that he is, gave me some stick time on the predator. After awhile
he took it back and proceeded to thermal it out of sight. Some where into this
flight, he gave it back to me to get some more stick time. Also during this
flight, he had to leave for a meeting.
Dave's first mistake was to give me the TX in the first place. The second was
deciding that because I had the afternoon off and would still be at the field,
he'd leave the predator with me, go do his thing, and then return. So, off
Dave goes.
Sometime later, the predator returns to mother earth, and I am doing hand
launches again. While I'm hand launching, I'm considering going up on the
high start to do some thermal hunting.
I launched (hand) the predator, did a 360 or two, and as I come around back
into the wind towards myself, I see that there is a metal soccer goal between
the predator and myself. At first I think, what the heck, I'll just fly
through it. I have this teeny little plane, and this BIG soccer goal. No
problem. As I approach the goal, I decide na, I won't play games with someone
else's plane and pull up to go over the goal. Suddenly I hear this horrendous
BONG!!!!! as the predator center punches the soccer goal and falls to earth in
two pieces. The sound is loud enough that it get's EVERYONE'S attention at the
field.
Damage inspection shows that the wing bolt sheared and there was leading edge,
and sheeting damage on the right side. Spar and ribs were intact. Hatch cover
lost the rubber band someplace. Small split in the fuse just behind the nose
block.
All this took place about 10 minutes after Dave left. He wasn't due to return
for about an hour. At about 1:45, everyone else was gone and I sat there
waiting for Dave's return. At 2:30, just as I was about to put the predator
in the car and leave, Dave arrives. Dave get's out of the car and I approach
him saying "bad news". Dave says "your kidding, what happened". I say "GOAL
POST". Dave shakes his head knowingly.
Picks up the wounded predator, puts it in the car, pulls out the Prodigy,
launches it, and GIVES ME THE TX. My first thought is that Dave is trying to
get out of the hobby and wants to blame it on someone else. But I guess not.
He's just a nice guy.
I really felt bad having to hang around for an hour and a half having nothing
to fly ( I meand dinging the predator), but seeing it fly again Sunday made
me feel better. He even let me fly it again. WILL THIS MAN NEVER LEARN.
Yesterday (this is getting to be a long note, but no sense making two notes)
I met Jim reith, Lemar, and Pete at the acton field. The intimidator was ready
to go. Winds were at least 20 to 25 MPH with higher gusts. First launch was a
bear as the plane popped off about half way up the launch and I had WAY too much
up trim. The Intimidator was porposing all over the place which, in 25 MPH
winds was interesting. I got it under control but had no altitude left and
just landed. Second launch was ok and some more trimming was done. Third and
last launch was pretty good and the Intimidator flew well. Even in the strong
winds of yesterday, it would still penetrate (with no balast) and was very
responsive and controlable. I think it will be a very good flying ship in more
reasonable winds and will work well on the slope. So far, I'm happy with it.
I'll even let Dave fly it.
|
1374.19 | The river was softer than the goalpost 8^) | ZENDIA::REITH | Jim Reith DTN 226-6102 - LTN2-1/F02 | Tue Oct 29 1991 08:24 | 5 |
| There are several rites of passage in Acton. One of them is hitting the
permanent soccer goals. We've ALL done it (landing in the net is FUN
8^). The next step is wandering through the swamp looking for planes
(or pieces). Oh, we didn't tell you about the swamp down below those
trees??
|
1374.20 | New Predator Instruction Manual | 18199::WALTER | | Tue Oct 29 1991 15:40 | 17 |
| Rev. 4 of the instruction manual is now available in the same directory
as before:
UPSENG::SPITFIRE:[WALTER.PUBLIC]PREDATOR_MAN_4.PS
Our group just moved into Salem NH from the Andover plant, and the
computers were jostled a bit in the move. If anyone has problems
accessing the file, let me know.
Rev. 4 Update:
--------------
The only major change in this version is the addition of a diagram
that (I hope) explains how the inboard spar is cut to match up with
the outboard spar. If this is still confusing, then I'm plum out of
ideas on how to describe it. I'm an engineer, not a tech writer!
Dave
|
1374.21 | Flash! TWO Predators fly at Bose (briefly...) | 18199::WALTER | | Tue Oct 29 1991 15:46 | 14 |
| Another Predator was sighted this weekend. Alan Ball brought his
plane to Bose for a bit of slope soaring. Unfortunately, the wind
was from The Treacherous Southwest, causing the lift to occasionally
drop to zero. During one of these lulls, when I had plenty of
altitude, Alan's plane dropped like a rock (did I mention that it's
even heavier than my bloated original?) and somehow he managed to
miss the slope and kiss the road at the bottom instead. The damage
was minor, but it took him out of action for the day. Too bad, I
was hoping to give it a try.
Keep it light! Light! Light!
Dave
|
1374.22 | Nice Plans Gepetto | WMOIS::HIGGINS_G | The Moeman | Wed Oct 30 1991 12:25 | 9 |
|
I got my copy of the new Predator plans from Lamar last night and
have to say....GREAT JOB DAVE !! I wasn't sure what to expect compared
to the piece meal plans I had but when I say the new ones.....WOW..
You've outdone yourself !! Now I'll print a copy of the rev 4 manual
and go to town.....
George
|
1374.23 | I second the great job!! | SALEM::PISTEY | | Thu Oct 31 1991 08:33 | 13 |
|
I too recieved my copy of the Predator plans from Dave.
Excellent job Dave. I have recieved plans from RCM that were
not as good, ( Firestreak , RCM 1983 I think) The instruction
manual is good and I've already read it through twice!. I may
just build two of these at once, sort of like competing against
myself to see which one comes out the lightest. I also like the
bit about useing a 25 foot piece of rubber for a small field
high start. Perfect for my "backyard" .
Regards
kevin p
|
1374.24 | All this and it flies great too! | ZENDIA::REITH | Jim Reith DTN 226-6102 - LTN2-1/F02 | Thu Oct 31 1991 08:44 | 11 |
| Personally, I find that the fuselage on a HLG takes the most abuse.
I've got three Gnome fuselages and which one is flying usually depends
on which one is the most repairable. While I've damaged the wing, it's
generally the fuselage damage that grounds me. I flew my Gnome after
taking out the leading edge on the soccer goal last year by just
removing the loose pieces 8^) I got in a few more tosses before having
to go back to work. It's always nice to have a spare fuselage at a
contest where you can just transfer the Rx and battery and fly (I
usually keep servos in two of them)
I'll agree with the quality. They're better than my RCM P-38 plans
|
1374.25 | Work Commences... | WMOIS::HIGGINS_G | The Moeman | Thu Oct 31 1991 12:22 | 15 |
|
I got to spend a little time in the shop last night and got started
on the Predator. I was able to build up the stab get it all sanded
and have the fin just about done.
Boy...the carbon fiber sandwiched between the (2) 1/8 sq. balsa stix
for the stab leading edge realing strengthens it up. Thanks for the
tip Lamar... I am also planning on adding "CF" between the spruce
stix used to reinforce the leading and trailing edge of the fin...
I'd like to keep the weight close to the recommended 15oz, but I'd
rather lean to a little added strength for a novices first fumbling
glider flights....
George
|
1374.26 | Predator_tip_templates.ps | ZENDIA::REITH | Jim Reith DTN 226-6102 - LTN2-1/F02 | Thu Oct 31 1991 12:44 | 4 |
| In case anyone else wants them, I mailed Lamar, Dave, and Mike the
aifoil.com generated templates for the tip ribs. I generated a set of 6
ribs, root=7", tip=6" with a straight taper. this gives you a pattern
for each rib.
|
1374.27 | thanks for update | RANGER::PITONIAK | | Thu Oct 31 1991 12:45 | 9 |
| Dave,
Thanks for the clerifications to the wing polyhedral
assembly process; if it was clear enough to sink into
my thick skull it qualifies you for tech writer of the year!
regards,
mike
|
1374.28 | How's about a copy | BBOVAX::DONAGHY | | Thu Oct 31 1991 16:43 | 7 |
| Hey Jim,
How about putting the airfoil (predator_tip_templates.ps) in this note.
Then us common folk could extract it.
Thanks ,
Bob in Pho
|
1374.29 | 2nd | WMOIS::HIGGINS_G | The Moeman | Thu Oct 31 1991 17:06 | 3 |
| Ya Jimbo,
I second Bob's reply.....
|
1374.30 | My apologies, it's long (predator_tip_ribs.ps) | ZENDIA::REITH | Jim Reith DTN 226-6102 - LTN2-1/F02 | Thu Oct 31 1991 17:11 | 379 |
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end
%%EndProlog
%%EndSetup
/S3014 [
% Similar to the S3021, it has lift and drag characteristics similar to
% the E193 and E205 but is improved in drag. Better than the S3010 or
% S3021 at very low Reynolds numbers (down to 60,000). Ideal for wing
% tips or HLGs. Falcon 880 uses a S3021 for the root to the tip panel
% and the S3014 for the tip panel itself.
1.00000 .00000
.99663 .00021
.98667 .00099
.97044 .00264
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.07864 .04741
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.00978 .01492
.00278 .00682
.00000 -.00003
.00284 -.00526
.01183 -.00972
.02610 -.01383
.04545 -.01731
.06973 -.02006
.09879 -.02204
.13239 -.02329
.17024 -.02386
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.89250 -.00367
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.97151 -.00124
.98699 -.00052
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1.00001 .00000
] def
AirfoilDict begin
%%%% begin first page %%%%
save
72 72 sc % set scale to inches instead of points
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/ribnumber exd
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/offsetmode 1 def
/frontholepoint rootfrontholepoint tipfrontholepoint seq fade def
/holeelevation rootholeelevation tipholeelevation seq fade def
AF rootthickness tipthickness seq fade thickness 0.25 10.75 chord
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AF rootthickness tipthickness seq fade thickness reverse 2.125 10.75 chord
labelfoil DrawCoords
mirrorpage
AF rootthickness tipthickness seq fade thickness 0.25 10.75 chord
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AF rootthickness tipthickness seq fade thickness reverse 2.125 10.75 chord
labelfoil DrawCoords
mirrorpage
gsave
1 1 copies 1 sub {pop copypage}for
showpage
grestore
} for
restore
end
%%Trailer
|
1374.31 | Pointer to Predator ribs PS file | 18199::WALTER | | Thu Oct 31 1991 17:12 | 7 |
| I have placed a copy of the Predator ribs PS file in my public directory:
UPSENG::SPITFIRE:[WALTER.PUBLIC]PREDATOR_RIBS.PS
Thanks to Jim Reith for generating the file, and Glenn Schrader for writing
the program.
|
1374.32 | How about Predators in UK? | NEWOA::NEALE | Ignotum per ignotius | Fri Nov 01 1991 06:01 | 12 |
| Dave,
I am coming over to your part of the world in a couple of weeks time. I
would very much like to pick up a copy of the Predator plans - saves
postage! Where are you based?
For any UK RC notes readers - I would be happy (if it is OK with Dave
himself!) to collect copies of these plans for you at the same time.
Any takers? Mail me (NEWOA::NEALE or Brian Neale @NEW) or call on DTN
774 6035.
- Brian
|
1374.33 | Predator migration | 18199::WALTER | | Sun Nov 03 1991 19:19 | 9 |
| I work in Salem, New Hampshire, live in Hudson, Massachusetts.
You can contact me through mail to make arrangements to meet.
(Egad! Predators migrating across The Big Pond? This is great!
But I just thought of something: Someone told me there's a
European plane of some sort called the Predator. Has anyone heard
of it? Do I have a copyright problem?)
Dave
|
1374.34 | Update | RANGER::PITONIAK | | Mon Nov 04 1991 10:11 | 7 |
| Dave,
Making great progress on my preditor. I noticed last nite that
the material list was missing the root rib 3/16 material; or
am i missing something obvious again???
mike
|
1374.35 | 3/16" root ribs | 18199::WALTER | | Mon Nov 04 1991 12:49 | 7 |
| Yep, that's another omission. I think I'll edit the instructions to
simply include 3/16" sheet for the root ribs. However, you can also
stack up a 1/8" to a 1/16" sheet and glue together. Or use three
1/16" sheets. Doesn't matter. But the ribs do need to be at least
3/16" thick so that the dowel is completely surrounded by wood.
Dave
|
1374.36 | I've built planes out of my scrap box 8^) | ZENDIA::REITH | Jim Reith DTN 226-6102 - LTN2-1/F02 | Mon Nov 04 1991 13:11 | 8 |
| Two stock 1/16" ribs sandwiched around one made from vertical grain
would be very sturdy and fit into the current wood. I also believe
there's enough 3/32" left after cutting the fuselage sides to get two
from there.
I always raid my scrap box for things like this. When I get done
scratch building, I generally have a couple of untouched sheets hanging
around begging me to start something else 8^)
|
1374.37 | poly rib question? | RANGER::PITONIAK | | Tue Nov 05 1991 11:37 | 8 |
| Dave,
Should the polyhedral rib be paralell to the inner panel ribs, or
the outer panel ribs?
thanks,
Mike
|
1374.38 | Yes ! I have it ! | ELMAGO::TTOMBAUGH | Janine T., come fly with me! | Tue Nov 05 1991 12:04 | 16 |
| I received my Predator plans. Looks good Dave.
What is the function of the longer rear fuse. and increased fin area?
To improve spiral stability?
I have a stock E205 Flinger wing, in perfect shape, which will make
an interesting comparision to the S3014, if I build the new one as
a 3014, but am leaning to the S4061 as I've had good results with
that, or even the E387 just to see what all the contemporary fuss
is over that being the hot "new" foil for HLG.
Actually the Predator must take its place in the building queue, and
frankly I've forgotten how many are ahead of it, but am shooting for
completion this decade. ;^)
Terry
|
1374.39 | Angle of polyhedral ribs | 18199::WALTER | | Tue Nov 05 1991 12:07 | 7 |
| Re: -.1
Probably doesn't matter much. It's only a few degrees of
difference. If you use my build procedure, the polyhedral angle
has already been set, and you're just placing the rib halves into
place. I think I ended up gluing them in at an angle half way between
the inner and outer ribs.
|
1374.40 | thanks | RANGER::PITONIAK | | Tue Nov 05 1991 12:16 | 3 |
| Dave,
Thanks..
|
1374.41 | No Man_4 yet | WMOIS::HIGGINS_G | The Moeman | Tue Nov 05 1991 12:20 | 9 |
|
Dave,
I'm having trouble copying the rev. 4 manual. Is UPSENG available
to copy from yet, and if not can you put the file in a copyable
location ??
Thanks,
George
|
1374.42 | "Spiral stability"? What's dat? | 18199::WALTER | | Tue Nov 05 1991 12:35 | 46 |
| (Reply to Terry...)
If you want to know how I came up with the modifications of the Flinger,
here's how the design process went:
First of all, I wanted more wing area. With 330 sq in, the Flinger
just seemed to drop out of the air too easily (how's that for scientific
observation?). And somewhere (maybe this conference) I read that
HLG's fly best with 400 sq in. So I just increased the chord from
6" to 7". I also used the S3014 airfoil because of a suggestion in
this conference.
Next, I felt the Flinger was a bit short coupled, way too sensitive
to elevator. As Helmut once commented, "it didn't groove in the air".
So I extended the tail boom, 2" I think.
Once I had decided roughly where the 40% point of the horizontal stab
and vertical stab would be, I needed to determine the area of each
surface. For this, I actually had to do some calculations! Helmut had
given me a rule of thumb, in his usual cryptic way: "0.4 and 0.03".
That's the "horizontal stab volume" and the "vertical stab volume".
These are the dimensions that seemed to work well for his planes.
The equations (don't remember them right now) for volume use the
wing span, wing chord, moment arm (that's the distance from the
wing 40% point to the surface 40% point), and surface area. The
hard part was translating the surface area to a usable shape,
especially for the fin, which isn't a simple rectangle. Matter of
fact, the fin ended up at 0.025 and it still looks big.
And the only noteworthy part of the fuse (other than making it as
narrow as possible) was to extend the nose a bit so less weight would
be needed to balance it.
When it came to setting wing incidence, I didn't have a clue,
scientifically speaking. So I used what most gliders seem to have,
1 degree of positive incidence. I should mention here that some
experimentation has convinced me that the incidence has a huge effect
on the glide of the plane. Get it just right and it seems to just
cover sky effortlessly, and long, low landing approaches are possible.
Get it wrong, and it's as if you put the brakes on.
So that's it. I know about as much about spiral stability as your
common mollusk. Most of the design was just educated cases and some
blind faith. It was a lot of fun, too.
Dave
|
1374.43 | | ELMAGO::TTOMBAUGH | Janine T., come fly with me! | Tue Nov 05 1991 13:03 | 8 |
| Thanks for the explanation.
Mollusks are noted for their high stability, so you're in good
company.
Another mod I'm considering is CF mat to replace some of the ply
doublers.
Terry
|
1374.44 | Paint Fuselage?? | RANGER::PITONIAK | | Tue Nov 12 1991 08:31 | 14 |
| Fellow Preditor builders,
I was considering painting the fuselage rather than covering it
basicly because my skills with monocote leave something to be
desired, but additionally for weight savings.
My concern is with what Dave mentioned in the building instructions,
regarding sealing the finger hole to prevent damage from wet
grass landings. Is there an epoxy based primer/paint that would fit
the bill here??
Thanks in advance
Mike
|
1374.45 | I vote for film instead of paint | ZENDIA::REITH | Jim Reith DTN 226-6102 - LTN2-1/F02 | Tue Nov 12 1991 08:39 | 5 |
| K&B and HobbyPoxy both make model epoxy paints. I'm not sure that
you'll come out lighter than monocoat by painting unless you simply
throw a coat on to seal/color without going for a smooth surface. I
honestly think paint will add too much weight (but with 4 servos in the
wings, what does it matter 8^)
|
1374.46 | Is this an F3B HLG? | UPSENG::WALTER | | Tue Nov 12 1991 11:27 | 2 |
| OK, I'll bite: do you REALLY have 4 servos in the wings??? Tell me
it ain't true...
|
1374.47 | 8^) | ZENDIA::REITH | Jim Reith DTN 226-6102 - LTN2-1/F02 | Tue Nov 12 1991 11:36 | 2 |
| Why do you think we're discussing catapult launching techniques in
another topic?
|
1374.48 | | UPSENG::WALTER | | Tue Nov 12 1991 12:55 | 23 |
| In honor of the DECRCM meeting tonight, I decided to bring in the
Predator so that people who are building one can get a look at the
finished product. Matter of fact, I thought it would be a good idea to
illustrate some of the wing details. So, I took it out at lunch time,
in strong winds and ferocious turbulence, and proceeded to expose some
of the "wing details". Well, OK, maybe the decision to show the inside
of the wing came AFTER the lunchtime flight.
A very short flight it was, too. I knew it was windy, but I've flown in
wind before. I realized it was turbulent after the first couple tosses.
An intelligent pilot would have stopped here. But I pressed on,
figuring I can handle it. The next throw got lots of altitude; the
plane topped out, moved about 20 feet into the wind, then all control
response just came to a halt. At the same time, an invisible hand
flipped it on its back and literally threw it into the ground. I mean
it was tomahawked! Must have been one of them "microbursts" the
airlines blame most of their accidents on. Yeah, it was a microburst. Only
once before have I seen one of my gliders change direction so fast.
Oh, well, more fodder for show and tell.
Dave
|
1374.49 | Hobbypoxy II | ELMAGO::TTOMBAUGH | Janine T., come fly with me! | Tue Nov 12 1991 12:56 | 13 |
| re .44
To seal the wood in and around the finger hole, just brush on a coat
of slow cure epoxy glue such as Hobby Poxy II. It can be thinned
slightly with alcohol in order to flow out more easily, but on such
a small area, thinning isn't really necessary.
I agree with the others, that a film covering will be lighter than
any sort of decent looking paint job.
BTW, what's this "wet grass" business ? Thought that was illegal. ;^).
Terry
|
1374.50 | Say it ain't so - 4 servos? | BBOVAX::DONAGHY | | Wed Nov 13 1991 13:12 | 9 |
| Regarding .45 , Does this glider realy have 4 servos in the wing?
Can someone give me the configuration before I order a set of plans.
EG. Two channel aileron / elevator ship with optional flaps/spoolers
Thanks in advance
Bob in Pho
P.S. Thankyou to Jim Reith for the postscript(airfoil) , muchos gracias !
|
1374.51 | no servos in the wings | KAY::FISHER | If better is possible, good is not enough. | Wed Nov 13 1991 13:33 | 10 |
| > <<< Note 1374.50 by BBOVAX::DONAGHY >>>
> -< Say it ain't so - 4 servos? >-
It ain't so. They were joking. It is a classic HLG.
Best with two micro servos and a micro receiver.
Bye --+--
Kay R. Fisher |
---------------O---------------
################################################################################
|
1374.52 | Yes, we were kidding (but now thaty you mention it... 8^) | ZENDIA::REITH | Jim Reith DTN 226-6102 - LTN2-1/F02 | Wed Nov 13 1991 13:57 | 5 |
| How ya doing, Bob. The Shadow still lives!
I was just kidding a guy who recently asked 347 questions when I new
his latest plane was a Predator. Polyhedral rudder/elevator and micro
servos are needed.
|
1374.53 | micro radio is best | UPSENG::WALTER | | Wed Nov 13 1991 15:56 | 11 |
| Thank God he's not putting 4 servos in the wing. You had me going
there!
The next rev of the instructions will have a few words on suggested
radio equipment. I designed the fuse around the Futaba micro radio:
R114H receiver, S133 servos, and 250ma battery. A bigger receiver will
most likely force you to deepen the fuse a bit. Mini servos might fit
as is, but standard ones will also force some dimension to change. And
a 250ma pack (or smaller) is your only chance to keep the nose nice and
narrow.
|
1374.54 | Bigger will fit (he said knowingly with a wink 8^) | ZENDIA::REITH | Jim Reith DTN 226-6102 - LTN2-1/F02 | Wed Nov 13 1991 16:20 | 11 |
| I used the S-133 servos and 225ma battery with my JR PCM 7ch Rx. One of the
nice differences in this Rx is that the plugs are on the end, not off
the top/side. One minor worry is that if the Rx slides back enough, it
could unplug something. It fit very nicely in the supplied space under
the front half of the wing and it balanced properly.
One other mod that I don't think I mentioned was that I used clear soda
straws (seem the lightest) a a Rx antenna tunnel through the tail which
allows me to pop the Rx in and out of the plane rather easily. This is
important since I have a limited number of Rxs to swap around. This is
from the Ol' Buzzard's book in the streamlining section.
|
1374.55 | Pred Mod Questions | RANGER::PITONIAK | | Mon Nov 18 1991 12:09 | 26 |
| Even though I may be just foolish enough to sqeeze 4 servos in
a preditor, I have no plans to do so right now. :-)
I have though of a mod I would like to try in a next
generation preditor though; and I would like to get some input
on from those that have seen other designs over their building
experience.
I would like to implemenmt a full flying stab like the chuperosa.
I borrowed the plans from Kay to try to gain some insight,
but I dont think that design would be applicable. The goal would
be to maintain the rigidity of the longerons in the rear, and some-how
integrate a fin assymbly into the fuselage without making the rear
too wide, or heavy. From here an approach like the chup would
work fine.
For those that would ask why, i'll add that the current design
is probably preferable, but I have quite a bit of difficlty with
covering the tail feathers first, and the mounting them. The goal
would be to make the covering of the fus/fin easier, and then just
slide the horiz stab on later.
Any inputs appreciated.
Mike
|
1374.56 | Fixed vs. Full flying | UPSENG::WALTER | | Tue Nov 19 1991 16:45 | 21 |
| The main reason I went with a regular stab rather than full flying
is weight. You need more stuff back there with the full flying, like
brass tubes and steel connecting rods, and all the reinforcements to
hold them in place. It adds up. I think the Chup designer tried to
compensate for that by using the open fuse structure in the back,
to reduce weight. (Chup owners: Is that open fuse a weak point?)
The advantage of the full flying stab is you don't have to worry
about wing incidence. When you trim the elevator, you are effectively
changing the neutral incidence. That's a nice feature.
But I'll reiterate my personal opinion here: weight is KEY! It's just
SO much easier to ride a thermal when the wing loading is low. And the
therms near the ground tend to be pretty weak. The plane can also be
thrown higher, with less pain in the arm.
If you aren't so concerned about performance from a hand launch, then
by all means try a full flying stab. Experimentation is fun! And so
far, no two Predators have been built alike.
Dave
|
1374.57 | List of owners of plans | UPSENG::WALTER | | Tue Nov 19 1991 16:49 | 27 |
| I've kept track of everyone who has been given copies of the Predator plans.
We're up to about 23 so far. Of that 23, 3 have actually been built. That's
probably a normal buy-to-build ratio!
James Armstrong Downeast Soaring Club
Ken Baker Downeast Soaring Club
Robert Cerchione Met at Salisbury glider contest
Bob Collins DEC
Tom Deloriea DEC
Kay Fisher DEC
Dave Fonseca DEC
Jeff Friedrichs DEC
George Higgins DEC
George Mills DEC
Dan Miner DEC
Randy Oswald DEC
Mark Patrolia Met at Salisbury glider contest
Lamar Phillips DEC
Kevin Pistey DEC
Mike Pitoniak DEC
Edward Prentice DEC
Lawton Read DEC (got plans from Lamar?)
Jim Reith DEC
Earl Timmons DEC
Terry Tombaugh DEC
Charlie Watt DEC
Bryan Whaley Met at Long Island glider contest
|
1374.58 | At least one person built two! | ZENDIA::REITH | Jim Reith DTN 226-6102 - LTN2-1/F02 | Tue Nov 19 1991 17:08 | 16 |
| One thing that I've done with the Fiberglass Chup is lengthened the
nose 2" to allow the radio to be moved farther forward to balance. I've
done that with several planes simply because I tend to build heavy and
it usually shows up in the tail. I'd rather move necessary weight
forward (radio) than add dead weight. I don't think the longer nose
hurts anything if the tail moment is kept standard. Any thoughts on
that?
The strength of the Chup tail seems to be dependent on how much care
you take to build the cross bracing. Good glue joints make a strong
structure. Ill fitting parts add nothing to it. It also has to do with
how much the tail gets whipped around. Catching a wingtip and whipping
the tail sideways seems to break the majority of the tails I've seen.
On my Gnome, I dropped it tail first a couple of times but only broke
the rear fuselage when catching a wing on something (the goal posts
come to mind)
|
1374.59 | Another Chup owner reporting, Sir! | ELMAGO::TTOMBAUGH | Janine T., come fly with me! | Tue Nov 19 1991 17:56 | 10 |
| The Chup tail seems plenty strong to me. Never broke mine.
Only thing that breaks is the little stab root fairings that are glued
to the fin.
I agree with Dave that you can't add too much lightness in an HLG.
All else being equal, a short nose glider will turn tighter/quicker.
Mainly noticeable on non-aileron designs.
Terry
|
1374.60 | Two more owners of plans | UPSENG::WALTER | | Wed Nov 20 1991 17:48 | 5 |
| Oops. I forgot a couple people. Two new suckers...er, owners, are:
Ajai Thir*mumble*ai DEC
Tom Rataski DEC
|
1374.61 | ADD ME! | RANGER::PITONIAK | | Fri Nov 22 1991 09:42 | 12 |
| COMPLETED PREDITORS..........
add me to the list!
It looks so pretty just sitting there on my work bench I almost
don't want to take it out for the inevitable.
Great design Dave, I love it!
p.s. Thanks for the inputs on the stab.
|
1374.62 | Ajai Thir*mumble*ai = Ajai ThirUMALai; can't make it simpler:) | HPSRAD::AJAI | | Fri Nov 22 1991 12:36 | 1 |
|
|
1374.63 | 8^) 8^) 8^) | ZENDIA::REITH | Jim Reith DTN 226-6102 - LTN2-1/F02 | Fri Nov 22 1991 12:41 | 1 |
| Gawd, guys... at least he didn't hyphenate it when he got married!
|
1374.64 | When *ARE* you going to let my wife into the US? | HPSRAD::AJAI | | Fri Nov 22 1991 12:49 | 1 |
| Now that you reminded me...
|
1374.65 | A possibility | WMOIS::WEIER | Wings are just a place to hang Ailerons | Fri Nov 22 1991 13:00 | 3 |
|
I bet the government would allow your wife in if you volunteered to
trade places with her! :)
|
1374.66 | Come again????????? | SNAX::SMITH | I FEEL THE NEED | Fri Nov 22 1991 13:04 | 6 |
| Ajai,
I wasn't aware any one in this notes file was responsible for
keeping your wife out of the country. 8^) <-------- semi serious
Steve
|
1374.67 | cap strip question | N25480::FRIEDRICHS | Keep'm straight 'n level | Mon Dec 23 1991 16:22 | 11 |
| Question for you predator builders...
How far back do the cap strips extend? All the way to the trailing
edge of the wing, or just the trailing edge of the rib??
Thanks!
jeff
(who has build the fuse and is already a bit worried about going near
a scale.. I REALLY tried to build it light! Honest!)
|
1374.68 | disregard last question | N25480::FRIEDRICHS | Keep'm straight 'n level | Tue Dec 24 1991 09:09 | 23 |
| OK, I talked with Dave yesterday and he straightened me out.. I didn't
look closely enough at the wing cross section, (Yes, dave, it is on
my plans..) thus my question really doesn't make any sense...
One other question though, is the LE to spar upper sheeting the entire
length of the wing?
Also, have people been using carbon fiber on the spars or no bothered?
I CF the spars on the inside surface but it did not seem to help the
strength nearly as much as the shear webbing did..
As for weight... I was at lechmere last night and they had these food
scales for sale for $7.99, and it weighs up to 16oz, or $9.99 up to
18oz. (1/2oz increments. It also has grams) I was so curious about
the weight that I bought one...
Currently, the fuse w/radio gear but w/o covering is a bit over 8oz.
The misbuilt wing *half* was about 1.5oz. Gee, maybe I will be able to
come in at about 16oz....
cheers,
jeff
|
1374.69 | CF rules! 8^) | ZENDIA::REITH | Jim Reith DTN 226-6102 - LTN2-1/F02 | Tue Dec 24 1991 09:15 | 10 |
| Jeff,
I used CF on the full length of the spars along with the sheer webs and
it really helped the wing strength. I don't think I'd build another
plane I intended to winch launch without CF on the spars (remember the
balsa snow storm in June?) If you're never going to put a tow hook on
it, don't worry about it but I think you need it if you're going to
zoom launch it even off a medium hi-start.
(I don't remember the LE sheeting)
|
1374.70 | CF not necessary in wing. | UPSENG::WALTER | | Tue Dec 24 1991 15:47 | 18 |
| I never did use any carbon fiber in the wing. It seems to be plenty strong
as it is. I've even winch launched the Predator without any problems. Matter
of fact, the wing seems to be the most rugged part of the glider... all my
repairs have been to the tail and the fuselage, especially around the tail
section.
The top wing sheeting is from the spar to the leading edge, for the full span.
That gives the wing a lot of strength and stiffness. Now, if you'd like to
try something different, maybe you could taper the top sheet between the
poly break and the tip to save weight. (I think the Gentle Lady wing is built
that way???) Or eliminate the sheeting entirely on the outboard panel. Reducing
the weight in the tip panels will probably enhance the handling and quickness
too. But, it'll break more easily.
Better yet, build two wings, one extra light, and a stock wing for use when
you're fixing the light wing.
Dave
|
1374.71 | slight correction | SNAX::SMITH | I FEEL THE NEED | Thu Dec 26 1991 07:32 | 5 |
| >>>> All my repairs have been to the tail and fuse.
EXCEPT when you leave it with me........8^)
Steve
|
1374.72 | I stand corrected | UPSENG::WALTER | | Thu Dec 26 1991 15:06 | 10 |
| >>> EXCEPT when you leave it with me........8^)
OK, ok, so my previous statement was a little inaccurate. The wing HAS taken
some damage. Once from a badly positioned goal post (Steve, how fast was that
goal post going when it hit you???), and before that from a
direct hit by a lead-sled Sagitta. I guess I was talking about damage incurred
during normal flight maneuvers, not special circumstances. Of course, when
Steve is flying, a normal flight maneuver IS a special circumstance!
Dave
|
1374.73 | Lead? | KAY::FISHER | If better is possible, good is not enough. | Mon Dec 30 1991 13:57 | 14 |
| > <<< Note 1374.72 by UPSENG::WALTER >>>
> -< I stand corrected >-
...
>direct hit by a lead-sled Sagitta. I guess I was talking about damage incurred
Hmmmmm - I have the only lead-sled Sagitta that I know about and
I don't remember hitting your predator? Could it be that someone found
a way to stuff more lead in the nose of their Sagitta than I did?
Bye --+--
Kay R. Fisher |
---------------O---------------
################################################################################
|
1374.74 | I thought you just went for boots 8^) | ZENDIA::REITH | Jim Reith DTN 226-6102 - LTN2-1/F02 | Mon Dec 30 1991 14:13 | 1 |
| It was the one from CRRC.
|
1374.75 | Are ALL Sagittas that heavy? | UPSENG::WALTER | | Thu Jan 02 1992 18:10 | 3 |
| This particular collision was with Bruce Schneider's Sagitta. It may not be
quite as dense as Kay's, but as sleds go it's right up there. The impact
put a slight crease in his nose, and nearly demolished my Predator.
|
1374.76 | Fuselage #2 | QUIVER::WALTER | | Mon Jan 20 1992 17:46 | 44 |
| I finally completed Predator fuselage #2. I'm a little disappointed
with the all up flying weight of 17 oz. I was hoping to get back down
to the 15 oz. range, and I'm a little mystified as to how it ended up
so heavy. I built it according to the latest plans, with only two major
departures: I used ply doublers that only extend to former F3 (under the
middle of the wing), and I added wing fillets to the saddle area. I can't
imagine more than .5 oz or so caused by the wing fillets.
There's a chance that the wing (from the original Predator) is the source
of the extra weight. After encounters with a CMRCM sign post, a speeding
Sagitta, and an Acton soccer goal post (Steve, HOW fast was that goal
post going...?!), the wing has taken on some extra mass, but I don't know
how much.
For you measurement masochists out there, here's how the weight distribution
panned out. All items were weighed after covering (Ultracoat); an O'Haus
three beam balanced was used for the measurements.
Predator #2 Weight
Item grams ounces
-------------------------------------------------------------------------
Fin, rudder, and fin fillets 10.4 .37
Stab and elevator 17.1 .60
Fuse (w/out control cables) 104.7 3.69
Wing 163.5 5.77
2 control cables + control horns 15.5 .55
Rcvr, 250mA, 2 servos, switch 123.8 4.37
Nose weight for balance 55.0 1.94
-----------------------
Total 490 g 17.3 oz
Hmmmmm. Almost 2 oz noseweight. Sounds kind of high. I used Ultracoat
on this fuse instead of Monocoat. Could that add significantly to tail
weight?
Dave
|
1374.77 | Lengthen the next nose... | RANGER::REITH | Jim (RANGER::) Reith - LJO2 | Tue Jan 21 1992 07:33 | 4 |
| Those fin fillets have a big moment arm. You might try extending the
nose slightly so the battery can move forward to offset the tail
weight. Really does seem a shame to add almost 2oz of nose weight to
balance it out. Seems to be the difference between 15 and 17ozs.
|
1374.78 | Antenna tube location | VSSCAD::WATTS6::TIMMONS | | Fri Mar 06 1992 08:11 | 5 |
| re .54
Jim, where did you locate the soda straws, in the same approximate
position as the plan location, ie lower corner of fuse or up higher?
If it is the lower corner, does straw interfere with your finger in
the finger hole. (question from a beginner rc'r).
|
1374.79 | Something else to consider - run it out the wing | RANGER::REITH | Jim (RANGER::) Reith - LJO2 | Fri Mar 06 1992 08:46 | 4 |
| Actually my straws start at the top of the finger hole and head down to
the floor at the tail. Use the lighter clear straws. On my next one I'm
going to run the antenna through the wing so I don't have the tail
heavyness from the wire behind the CG (just a thought)
|
1374.82 | Zap! (Not the glue...) | QUIVER::WALTER | | Thu Apr 30 1992 18:26 | 32 |
| Do I have to tell the story? I'm embarrassed enough as it is.
In a nutshell, I broke the cardinal rule about staying away from power
lines and put my Predator right into a power pole. Worse, it stuck...
one wing panel came fluttering down, but the rest of the plane was
nicely nestled in between the power pole and some high voltage lines.
How do I know they were high voltage? Because we observed little
lightning bolts dancing through the wing every couple seconds. But that
seemed to stop eventually. I nervously looked around for strangely
dark houses and half expected a Conn Edison truck to pull up at any
instant, but no one seemed to notice. Although it's hard not to notice
grown men standing in the middle of the street and throwing rocks at
a power pole.
We eventually graduated to golf balls, and I nailed that thing many
times, knocking off the tail and placing a divit or two in the fuse...
but it didn't budge. Right about this time I felt roughly 2" tall. I
had to leave it up there and go back to work. After work, Jim Reith
went back down to the field, and bless his soul, threw softballs at it
for 15 minutes until it finally was dislodged and came down. Apparently
he got a standing ovation from the soccer players at the field.
The damage is really not too bad, considering the abuse it took from
Top-Flite DDH and Ben Hogan Plus. Most amazing of all... the receiver
still works! Those Futaba R-114H receivers may now be specified
resistant to 14,000 volts!
Dave
PS: Earle, are you ready for me to test fly your new Predator? What
voltage is it rated for?
|
1374.86 | I like the 2 week trend! :) | WMOIS::WEIER | Wings are just a place to hang Ailerons | Fri May 01 1992 08:45 | 16 |
|
DW1,
The DW's have been having a tough year when it comes to crashes.
The good news for you is that I still have a comfortable lead in #
of crashes since January 1st. The bad news is that the crashes seem
to be migrating towards you in the last two weeks ( Gremlin, and
Predetor), and BTW, that works for me! :)
I don't know what all the fuss is about Futaba recievers, my AM
Futaba performed flawlessly at C-mass while JR FM's and PCM's were
getting hit left and right, now yours is able to take a 14,000
volt lickin, and its still tickin! :)
DW2
|
1374.87 | Don't Rave about AM Receiver | LEDS::WATT | | Fri May 01 1992 09:32 | 12 |
| Just don't try the 23 channel test with that AM receiver! By the way,
birds and such sit on those wires all the time so it isn't hard to
imagine why the receiver would get away with it. I saw a thing in MA a
couple of years back where a U-Control Combat plane took off with it's
steel lines attached and shorted out a big transformer, causing a
blackout and a bill to the AMA of 30K.
Bummer
Charlie
|
1374.93 | The Nicest Predator | QUIVER::WALTER | | Thu May 07 1992 18:44 | 18 |
| This is a sad day for me. I have cast my eyes upon a Predator that
looks nicer than mine ever did. Earle Timmons, a newcomer to RC, built
a Predator from my plans for his FIRST airplane, and did a spectacular
job on it. It took me at least 3 airplanes to get the covering as
smooth and tight as on Earle's plane. There isn't a wrinkle to be found
on it, and even the nose contouring is seamless.
The only changes he will have to make before getting airborne are to
add some noseweight (he even pre-hollowed out the nose block just in
case!) and reduce the throw of the elevator (which is currently set up
for the kind of throws used by Eric and the Snowman).
My compliments to Earle for a fine job of craftsmanship! Now it's time
to learn to fly this beast, and I can't wait to get it in the air.
Let's see, where's the nearest telephone pole...?
Dave
|
1374.94 | Convert to Electric? | LEDS::WATT | | Fri May 08 1992 09:12 | 7 |
| Dave,
Are you planning to convert his to Electric also? If you use metal
foil covering, you can improve the special effects the next time you
drop in for a "charge". :-)
Charlie
|
1374.95 | First flight for pilot and aircraft | VSSCAD::KEPNUT::TIMMONS | | Wed May 13 1992 14:55 | 20 |
| Well, my ship finally got into the air for the first time. In the
cockpit was "Captain'" Dave Walter. Thanks Dave!
This was also my first time flying RC. Dave hi-started the thing
and passed the controls to me. Pretty scary at times. I sure hope I
will be able to fly 1/10 as good as he! (loved those 3 loops you did
Dave!). Actually, the 3 loops were unintential. I initiated the loop
do to being a beginner then handed (threw) the xmitter at Dave. I
thought it was really neat, Dave making to more loops until I saw him
running toward the plane. We don't know what happened except that the
antenna may have got snagged in the elevator. Radio is a brand new
Futaba Conquest.
After that, he folded the antenna along the fuse and taped it. Flew
again and he found a thermal. Really exciting to see your fruits of
labor climbing still higher.
I think I'm hooked!!!!!!!!!
ps. Met Mike Ptoniak there for the first time. Mike, I'm impressed with
your flying after only a year at it!
Earle
|
1374.96 | Another Predator joins the fold | QUIVER::WALTER | | Thu May 14 1992 00:20 | 24 |
| The latest Predator flies just fine. Earle did a super building job.
All I needed to do to trim it was eyeball the surfaces. Another click
or two of down trim in the air and it was trimmed out. It launched on
the high start like it was on rails, a good indication that the wing is
straight and true. In spite of the overcast sky, there was some good
lift around, so I would ride up a thermal, hand the box to Earle, and
when it got low I'd take the box back and find another therm and go
back up. It worked out really well. Earle has begun that climb up the
learning curve.
Earle's Predator felt exactly like mine with my new wing (the one that
I actually built to my own plans). I still prefer the way the older
wing flew. With more dihedral, the old wing was much more responsive
and seemed to lose less speed in the turns. I think I'll hack off the
outer wing panels on my new wing and reattach them at a higher dihredal
angle, see if it improves the performance.
By the way, while we were flying today a fire engine pulled over to
watch for a few minutes. At first I thought they were going to accuse
me of flying into telephone poles, but they were just interested in the
planes (Generic Question #1: "Hey, how much does one of those things
cost?", Generic Question #2: "Where's the motor?", and Generic Question
#3: "No motor? How does it fly? Do you have to wait for wind?").
|
1374.97 | And another one flys | N25480::FRIEDRICHS | Keep'm straight 'n level | Mon Jul 06 1992 10:15 | 48 |
| Well, my Predator is finally finished. I built foam cores for it and
covered it all in monokote. Total weight (including 1.8oz of nose
weight was 18oz (arg!). I have backed off on the noseweight a little
though.
My first flights were Friday morning. I took about a dozen tosses
before I broke the front dowel. I had used a smaller dowel. It had a
real tendancy to stall. Also, the elevator linkage was a little sticky
so my slow reactions were amplified.
I went home and replaced the dowel with a larger one. I also put some
graphite on the pushrod. I also (wrongly) added some nose weight to
try to correct the stalling. I headed out to the field in the
afternoon again. I took maybe 1/2 dozen more tosses, but found the
stalls to be worse. Luckily, I did not damage the plane, but I did
decide to put it away until I re-read some of the glider triming notes
and newsletter articles.
I relearned what I should have already known about dynamic balancing of
the plane and removed some of the nose weight before I started flying
on Sunday. This helped the stalls a lot! I finally got it to fly
without (un-induced) stalls. It was actually doing pretty well as I
played with the nose weight some more.
I did notice that it turns better to the right. Sure enough, there is
a bit of a twist in the rudder. DW2 filled me in on another trick..
Before attaching the fin, put a pin in the nose of the plane and run a
string from the pin, around the fin and back to the pin. Now you can
attach the fin keeping both sides of fin in contact with the string.
Ifone or the other doesn't touch, then the fin is not straight.
After a bunch of flights, I finally broke the wing hold down block and
called it a day.
I should be able to take much of the twist out of the fin with the
monokote. The hold down is already re-glued. This week I plan on
putting the tow hook in and try some up-start flying with it.
Overall, I am only some-what happy with how it came out. There are
more than a few mistakes and it is too heavy, but it will do for now.
I also already have a lighter set of sheeted cores ready for finishing.
Perhaps I will save a bit more weight with these.
In all though, I (re)learned a lot and that is always good.
cheers,
jeff
|
1374.98 | Check for wing warp | QUIVER::WALTER | | Tue Jul 07 1992 18:25 | 21 |
| Jeff,
Mine is flying at 18 oz. right now. Granted, it isn't the ideal weight
(it flew MUCH nicer at 15 oz.) but it still flies pretty well and I
occasionally ride a thermal up. If you built the dowel and hold down
block the way I show in the plans, the plane will disintegrate before
those pieces break. (Me and a power pole proved that...)
If you find that it tends to always turn one way in flight, the fin
alignment may not be the only cause. Check the wing for any warps by
holding the bottom side up and sighting down the dihedral breaks. It
doesn't take much warp to cause it to turn. You can also put the plane
in a dive, then pull up, and see if it comes up straight or to the
side. Whenever the plane won't fly straight, I've found a warped wing
is almost always the cause.
Glad to hear it's flying! Maybe we can get together some time so I can
see this foam-wing Predator.
Dave
|