T.R | Title | User | Personal Name | Date | Lines |
---|
304.1 | why powerless glide landings ? | VIDEO::OSMAN | type video::user$7:[osman]eric.six | Thu Jun 25 1987 18:04 | 9 |
| How come there's so much talk about non-power-glide landings ?
It's not that it doesn't make sense to me. The shuttle does it.
I guess it's been proven to work.
But if it's so great, why aren't jet planes designed to land that
way ?
/Eric
|
304.2 | i was impressed | AMULET::STOLOS | | Thu Jun 25 1987 20:01 | 10 |
| last may when i was in wash. i was at the air and space mueseum.
there they had and exhibit of precursers to the shuttle, the first
model there was a wind tunnel model of Saenger's space plane.
the exhibit said that they had gotten as far as designing the
propulsion system and had done some limited tests before the war
ended, i was really amazed that the german's had such visionaries
in the 1940's but then again it was probably meant to bomb
new york with guess what kind of bomb that was also being reseached.
we were lucky if they had more time it could have been....
SPRINGTIME FOR HITLER AND GER-MAN-EEEE.
|
304.3 | safety and cost | ENGGSG::FLIS | | Fri Jun 26 1987 08:48 | 17 |
| RE: .1
The reason for non-power glide landings is weight saving from not
having to carry the fuel. The reason that jet planes do not employ
the same method is because of safety.
Added weight, on a spacecraft, adds mucho bucks to the cost of the
craft and the cost of flying it. This is not as noticable on an
aircraft, as it is designed to carry its own fuel during atmospheric
flight (The shuttle is not - again, to make it so would add too
much weight). Also there is the safety factor. The shuttle, and
similar craft, MUST land on the first try -- no fuel for a second
attempt. You wouldn't get *ME* on a jet that only had one shot at
a landing....
jim
|
304.4 | Cost first, safety second | MONSTR::HUGHES | Gary Hughes | Fri Jun 26 1987 09:45 | 15 |
| Jim is correct in .3. The shuttle was originally planned to jet
engines for final approach and landing but that got canned, mostly
for cost reasons.
As it exists now, the shuttle's descent is carefully planned by
a computer program called Energy Management System (runs on a VAX)
that determines the glide path so that the shuttle will alnd at
the right place with the right velocity. There is a very narrow
margin between stall speed and max safe landing speed. Any unplanned
flight deviation could result in significant landing damage to the
orbiter.
Yes it works. But it is not at all fault tolerant.
gary
|
304.5 | if powerless landings are dangerous, will NASA be allo | VIDEO::OSMAN | type video::user$7:[osman]eric.six | Mon Jun 29 1987 17:25 | 8 |
| This idea of having just ONE CHANCE to do the powerless landing sounds quite
dangerous.
If powerless landings are rejected for aircraft due to safety, then in light
of the Challenger loss and increased safety awareness, will NASA still be
able to get away with powerless landings in the next shuttle flight ?
/Eric
|
304.6 | | JETSAM::ANDRADE | The sentinel (.)(.) | Mon Jun 29 1987 18:04 | 8 |
| re .5
In this case economy is better regarded then safety. Just think,
how much it would cost the U.S. to give the shuttle just a second
landing option.
And in this point in time I agree with them, just as long as they
crew it with people who know the risks and are paid to take them.
|
304.7 | Whats wrong with one shot landings? | WARSAW::CHEETHAM | | Wed Jul 01 1987 14:00 | 7 |
| Us sailplane pilots have been living with the idea of just one shot
at landing for years,often in an unknown field with just a quick
look from the air to size the correct approach path etc (then we're
only doing 60 kts)
Dennis
|
304.8 | Gliding brickyards | VINO::DZIEDZIC | | Wed Jul 01 1987 19:22 | 10 |
| Yeah, but most of your garden variety sailplanes have at least
an order of magnitude better glide ratio than the shuttle, and
have no where NEAR the inertia built up. The shuttle is, to be
succinct, a flying brick. (I remember hearing figures for the
glide ratio of 1 foot of forward travel for 10 feet in drop in
altitude, or somewhere in that area.)
Oh, I also suspect your approach speed is a small fraction of
the shuttle's.
|
304.9 | Not a bad Glider | WARHED::CHEETHAM | | Thu Jul 02 1987 10:02 | 9 |
| 1 in 10 ain't that bad. The average club sailplane has about 1 in
25,the hot ships around 1 in 40. As for inertia,who cares when you've
got Edwards AFB to dissipate it in. What makes an unpowered approach
easy or difficult is the amount of approach control that the vehicle
has. I don't know how good the shuttle's approach control is but the flaps
and airbrakes certainly LOOK big enough. The point of 304.7 is not to
say that unpowered approaches are easy but to express the opinion
that with craft such as the Shuttle, Hotol etc the unpowered approach
is one of the lesser hazards.
|
304.10 | | CLOSUS::TAVARES | John--Stay low, keep moving | Thu Jul 02 1987 11:15 | 11 |
| No, the glide ratio of the shuttle, using your terminology is 10
in 1; the previous reply said that the shuttle travels 1 foot
forward for every 10 feet of drop. Or, are you saying that a
glider drops 25 feet for each foot forward?
By the way -- and I know this is a tempting rat-hole; but I saw
the IMAX (kind of a very large screen cinemascope) show up in
Denver a few weeks ago where they showed a sailplane film. They
put the camera in the cockpit and gave you a real pilot's eye
view. Never knew the sailplanes were capable of such high
performance! Must be a blast...
|
304.11 | Who wants to fly a brick? | WARDEN::CHEETHAM | | Thu Jul 02 1987 13:41 | 9 |
| 10 in 1 ohhhmygod,a rubber stamp does better than that,can anyone
confirm this? It certainly seems to flair O.K.
To follow down the rathole,modern sailplanes do have a very
good performance. I've been to 20,000ft and been round a 300 kilometer
triangle (not at the same time) and there are a lot better pilots
than me around.
Dennis
|
304.12 | out of context | ENGGSG::FLIS | | Thu Jul 02 1987 14:46 | 18 |
| re: .many...
the 10 in 1 glide configuration is correct, though stated out of
context.
The shuttle enters what is known as 'glide configuration' at a very
high altitude (shortly after reentry). 'Glide configuration' is
that time when the shuttles control surfaces are activated and
effective. This mode is entered at about Mach 11 to Mach 12. This
is when the 10 in 1 glide ratio is seen. As the shuttle enters
denser air, the glide ratio levels out to something more in line
with that of a gliding craft.
Rest assured that the shuttle does NOT make a landing approach with
a 10 to 1 glide (drop?) ratio!!!
jim
|
304.13 | Re: Flying Brickyard | CLT::JOYCE | | Thu Jul 02 1987 17:03 | 3 |
| This will sound outrageous, but the figure 4-1 sticks out in my
mind. I will have to look this up. Yes, talk about lead balloons!
|
304.14 | Slightly aerodynamically efficient brick? | WARHED::CHEETHAM | | Fri Jul 03 1987 12:09 | 12 |
| 4 in 1 still sounds a bit drastic. Watching on the box it looks
about 1 in 5 which is about the same as the average Spam Can(Piper
Cherokee etc). This again is not to bad with proper approach control,
Student pilots studying for a British PPL (Private Pilots Licence)
are expected to demonstrate a successful simulated engine failure
as part of the general handling test,the power failure being applied
unexpectedly by the examiner.
The actual landings carried out by the various shuttle pilots
are certainly impressive whatever the performance of the vehicle
(I didn't know I had landed until I heard the applause).
Dennis
|
304.15 | Not so much glide, as plummet | MONSTR::HUGHES | Walk like an Alien | Sun Jul 05 1987 13:42 | 11 |
| On final approach to the Cape, the glide ratio is about 4.7:1, i.e.
1 foot down for every 4.7 feet forward. Airspeed is about 210 mph.
This may be with a payload.
As the shuttle enters appraoch and landing phase, i.e. lined up
with the runway and at about 20,000 feet it enters a steep descent
phase with a glide slope of 22 degrees. During this phase, its vertical
speed is over 140 mph. It would overtake a skydiver in free fall!
(usual terminal velocity of a skydiver is about 120 mph)
gary
|
304.16 | Yep, it's steep | SKYLAB::FISHER | Burns Fisher 381-1466, ZKO1-1/D42 | Mon Jul 06 1987 21:27 | 22 |
| I have seen the shuttle land at Edwards AFB (Columbia, Spacelab
I), and I can confirm from visual observation that it is indeed
heading for the ground hell-bent-for-leather. I have a photo which
is quite incredible. I remember keeping the camera level, but of
course there are no landmarks in the picture, so I could have been
faking it.
A little babbling: If you remember, Spacelab I was the flight where
one of the GPCs (computers) died just before they were planning
to reenter, so they were waved off. It took more than one or 2
orbits to get it fixed, so EAFB had rotated out from under the orbit
too far. However, Spacelab had a larger inclination than EAFB's
lattitude, which meant that after a few hours, EAFB came into range
of the *decending* segment of the orbit. This is the way they landed.
The significance of this is that the shuttle approached EAFB from
the NORTHwest rather than the SOUTHwest and ended up doing nearly
a full circle around the HAC (heading alignment circle) rather
than just a fraction. This meant that they went *right* *over*
the parking lot where I was. What a view!
Burns (viewer of STS-1 liftoff and SL-1 landing and hoping for more)
|
304.17 | You don't really mean 1:10??? | CRVAX1::KAPLOW | sixteen bit paleontologist | Thu Jul 09 1987 19:14 | 8 |
| 1:10 sounds quite wrong to me, Jim. That would be almost a
vertical dive. I don't think they ever come down THAT steep. My
recollection is that the shuttle has a 2:1 glide ratio, and on
final aproach it pulls back to the 5:1 number that Gary refered
to. 2:1 would be close to Gary's 22 degree figure. Some of this
improvement is from ground effect; you can see how the shuttle
just hangs above the runway and slowly drops in its last few
seconds before touchdown.
|
304.18 | 1:10 *AND* 10:1 | ENGGSG::FLIS | | Sun Jul 19 1987 14:53 | 9 |
| RE: .17
1:10 is correct. But understand that this is at the begining of
the glide, when the craft is in *very* sparse air. In fact, from
what I have heard, the ratio does a complete flip sometimes durring
the landing (eg: at times the glide is 10:1) Probably the greatest
glide delta of any craft known.
jim
|
304.19 | Could HOTOL be threatened with cancellation? | DICKNS::KLAES | The Universe is safe. | Thu Aug 06 1987 08:53 | 15 |
| VNS MAIN NEWS: [Richard De Morgan, Chief Editor, VNS]
============== [Basingstoke, England ]
UK News
-------
ZIRCON spy satellite project abandoned over fears that technology would
be obsolete when it was completed. Meanwhile, British space projects have
been thrown into disarray by the resignation of the Director-General of
the BNSC: ESA warn that industrial contracts are dependent on upfront
money from countries; the BAe/Rolls Royce HOTOL project, which could have
cut launch costs by 80%, will probably be transferred to the US.
<><><><><><><> VNS Edition : 1375 Thursday 6-Aug-1987 <><><><><><><>
|
304.20 | British Aerospace still interested in HoToL | DICKNS::KLAES | Through the land of Mercia... | Wed Mar 09 1988 10:16 | 65 |
| From: [email protected] (ERCF08 Bob Gray)
Newsgroups: sci.space
Subject: There's hope yet
Date: 7 Mar 88 17:42:54 GMT
Organization: I.T. School, Univ. of Edinburgh, U.K.
Just when you thought the UK space effort was dead and buried...
One of the UK's computer trade newspapers "Computer weekly"
carried a front page article on Feb 25th edition entitled:
"Space project offers boost to software work".
I quote some excerpts from it.
"British Aerospace, the principal architect of the HoToL
programme - the UK's answer to the space shuttle - has asked
eight software houses to help it develop the software
technologies required to make the programme a reality."
"Software productivity and reliability are the key issues if
British Aerospace is to build the command and control system
for HoToL in an acceptable development time. Using existing
tools would require 3,000 worker years of effort - BA wants
to reduce that to 300."
"The HoToL programme to produce a re-useable reansit van
for the 21st century requires twice as much code as the
current all-electronic planes."
"It is also planned to cut down the size of team required to
fly the HoToL van. ... it takes 5,000 people to operate
the US shuttle."
"Over the next few months the club of software eight software
houses will iron out a programme of research. ... BA has
already set up another such club, to work on another
technical issue for HoToL - advanced material."
"HoToL needs some 5 billion pounds investment over
the next 10 years."
It is worth noting that one of the software houses, Logica, was
the main candidate do be awarded the contract by ESA for the software
systems on Columbus. (The ESA module of the US space station). Logica
had already spent large sums of money on preliminary research, before
the UK Government finally pulled out of the project a couple of weeks
ago. This was the only one of the three ESA special projects the UK
didn't give a definite no to at the ESA meeting last November. (Hardly
encouraging private enterprise).
Other developments in the last couple of days worth noting.
1. BA has put in a bid to buy the UK Government owned car makers,
previously known as British Layland (amongst others).
2. BL has close ties with Honda.
3. Honda has no aerospace expertise, unlike other Japanese car
makers, and has expresed an interest in entering the field.
I leave it to you to work out your own conclusions.
Bob
|
304.21 | UK will not fund HOTOL | MTWAIN::KLAES | Know Future | Tue Jul 26 1988 10:57 | 7 |
| Today's VOGON News says that the British government has declined
to fund the HOTOL spaceplane.
Nothing like progressive thinking, is there?
:^(
|
304.22 | it can (will?) happen here | BOSHOG::ALLEGREZZA | George Allegrezza @ NRO | Tue Jul 26 1988 11:04 | 5 |
| Re: -1
If you like that idea, you'll love President Dukakis. The recently
approved Democratic party platform calls for cancellation of the
Aerospace Plane, ALS, and work on advanced shuttles.
|
304.23 | I am for a real Station | PARITY::BIRO | | Tue Jul 26 1988 14:20 | 10 |
| NO DUKES if you want a real space station
It looks like he thinks we can get by without a permanently manned
space station
I think the answear is we need both, I hope he does not put us backwards
with the debates of man vs unmanned again
|
304.24 | forget about a US manned space program | STAR::BANKS | In Search of Mediocrity | Tue Jul 26 1988 15:10 | 8 |
| This is great. I think we've found the one Democratic candidate
who's anti-space program. We already know the Republicans want
nothing to do with a space program, unless directly related to SDI.
What now? A B-1C with a few thousand JATO bottles strapped to its
belly?
This is making me sick...
|
304.25 | Maybe that's the next big step | SARAH::BUEHLER | Use your braims. | Tue Jul 26 1988 15:48 | 7 |
| It might be a good thing if the U.S. space program got scrapped. If
space is really all we claim it is, then private industry would step
in, right? We're kidding ourselves if we think that any sort of a
majority of the people in Washington are thinking of the future of
mankind.
John
|
304.26 | Sigh... | SNDCSL::SMITH | Fezzik, tear his arms off. | Tue Jul 26 1988 16:57 | 10 |
| Well, ideally NASA is getting out of the commercial launch business,
DOT and others have been told to stop restricting private launch
services, and private enterprise will take care of the rest.
If you believe that the beaurocracy is really going to loosen the
reins on private launch companies, I've got a bridge you might be
interested in.... Of course if you are one of the biggies in teh
aerospace community already, it might be a little different.
Willie
|
304.27 | How HOTOL is powered for flight | MTWAIN::KLAES | Know Future | Wed Jul 27 1988 10:44 | 15 |
| VNS MAIN NEWS: [Richard De Morgan, Chief Editor, VNS]
============== [Basingstoke, England ]
Science, Technology, Medicine, and Nature
-----------------------------------------
Some of the details of HOTOL, the revolutionary proposed space vehicle
which the govt has declined to fund, have now become available and are
reported in The Times. The engine, the Rolls Royce RB545, is initially
powered by liquid hydrogen and air for the first 10 mins after the
takeoff at 250 mph from a rocket-powered sled. At Mach 5 it swiches to
LOX as the oxygen supply.
<><><><><><><> VNS Edition : 1620 Wednesday 27-Jul-1988 <><><><><><><>
|
304.28 | More details on HOTOL | MTWAIN::KLAES | No atomic lobsters this week. | Thu Sep 29 1988 13:54 | 29 |
| Newsgroups: sci.space
Path: decwrl!labrea!rutgers!rochester!dietz
Subject: Info on HOTOL
Posted: 27 Sep 88 20:01:10 GMT
Organization: U of Rochester, CS Dept, Rochester, NY
I've just read an article about HOTOL by B. R. A. Burns, the
project manager at British Aerospace. The article appeared in
Interdisciplinary Science Reviews, 13(2), 1988, pages 171-179. The
article was apparently written before the British government decided
to halt funding.
The article explains a bit about the engines, although they are
still classified. The engines cool and compress incoming air, but
apparently don't liquify it. The compressed air is used in dual-mode
rockets (the other oxidizer being LOX, of course).
Also, the article explains those funny protuberances on the back
of the air intake thar were apparent in the picture of the HOTOL model
that appeared in AW&ST some time back. On the trajectory the HOTOL
flies, it needs a larger air intake the faster it goes (this is unlike
a conventional supersonic plane, which needs a larger intake at low
speed). The protuberances are vents to release excess air at lower
speed. This also explains why HOTOL does not continue to breath air
above Mach 5: The air intake would have to be too large.
Paul F. Dietz
[email protected]
|
304.29 | always the best man, never the groom | FOOT::OTTEN | Evolution in Action | Thu Oct 27 1988 06:33 | 24 |
| The latest thing to enter the HOTOL arguement -
(Flame on)
The Engine design is classified, and the govornment has refused
to put up any more funds for the next stage of development (ONLY
5 million pounds)
So:
We aren't going to do anything to it (The UK) as RR and BA aren't
prepared to invest that sort of money without some sort of external
backing, and we can't get anyone else to do the work (IE sell the
design to USA or someone else) as the engines have "distinct military
possibilities"
(5 million pounds - is that 1/2 a TRIDENT, or 1/4) - if we built the
engine ourselves, we wouldn't need to buy Launch systems from the
states, (which hopefully we'd never use) AND we'd have a commercially
viable ??service only?? product.
Yours,
Angry of Basingstoke
(Flame off)
|
304.30 | Damn the British government | JANUS::BARKER | Jeremy Barker - Reading, England | Thu Oct 27 1988 08:02 | 17 |
| Re: .29
I don't know where this information came from, but unless it's very recent
it's wrong.
Last I heard a few weeks ago was that British Aeerospace and Rolls-Royce
had decided that they could spend some more money on it and there was also
some other non-governmental source of funding.
I must say that the British government's attitude to scientific research is
extremely negative. In the nuclear area not only have they announced that
fast reactor research will be terminated (the British program is perhaps
the world's most successful), but the latest leaks indicate that fusion
research will be completely cancelled as soon as the JET program ends in 1992.
jb
|
304.31 | Gone forever, or what? | HEEP::PETTEFAR | | Tue Sep 26 1989 12:03 | 5 |
| Does anyone have any further info on HoToL?
Cheers.
Nick Pee
|
304.32 | Status of HOTOL | VOSTOK::LEPAGE | Truth travels slowly | Tue Sep 26 1989 12:32 | 19 |
| Re: .31
Last I heard the project is still underway. There are also studies
being performed to see if an air launched version HOTOL would make a
better design (the present baseline design calls for a sled launching
mode). The Soviets have stated (and possibly formally offered by now)
that the new An-225 aircraft would be a suitable platform for air
launch.
The air launch mode is being examined because one of the major
problems with the current baseline design is that it can not make an
emergency landing fully fueled after a sled launch because its weight
would exceed the limits of the landing gear (stronger landing gear would
weight too much for HOTOL to carry any useful payload). In an air launch
there would be the option to return the HOTOL if some problem arises
before it is released. In addition, an air launch could potentially
increase the payload capability (or conversely be used to lighten the
craft, etc.)
Drew
|
304.33 | Wonderful! | HEEP::PETTEFAR | | Tue Sep 26 1989 12:46 | 4 |
| Thanks for the info. Have any kind patriotic souls decided to offer
any funding?
Nick Pee
|
304.34 | | STAR::BANKS | Zoot Mutant | Wed Sep 27 1989 18:07 | 4 |
| Yuck! I can just see it now: Fuel tanks with ejection mechanisms.
(Just one of those little details (emergency landings, fully loaded) that never
even occur to "civilians" like me.)
|
304.35 | HERMES to have Soviet ejector seats | WRKSYS::KLAES | N = R*fgfpneflfifaL | Mon Mar 26 1990 11:56 | 27 |
| From: [email protected]
Newsgroups: sci.space
Subject: Hermes crew escape system
Date: 26 Mar 90 15:06:18 GMT
Organization: The Internet
From: Lutz Massonne +49 6151 886 701 ESC1325 at ESOC
To: [email protected]
Subject: Shuttle escape
For the European Hermes spaceplane it was decided (according to newspaper
reports) to buy the Soviet ejection seats developed for the shuttle Buran.
The ejection seats will enable the crew to eject during the first 90 seconds
of the flight, placing them 500 m away from Hermes in 2 seconds.
Ejection will be possible up to 30 km altitude and a velocity of
3000 km/h.
Regards, Lutz Massonne
+===================================+===============================+
| Lutz Massonne | [email protected] |
| | |
| |This mail expresses my personal|
| Robert-Bosch Str. 5 |opinions only and is in no way |
| D-6100 Darmstadt, FRG |official or reliable. |
+===================================+===============================+
|
304.36 | This is gonna hurt | ANVIL::BUEHLER | Art is Science elevated | Tue Mar 27 1990 02:46 | 6 |
| Wait a second. 500 meters in 2 seconds? Let's assume that I can get the
ejection assembly moving at 250 meters per second. That's 540 miles per hour.
I don't have the physics to deal with this, but if 9.8 meters/sec� is one G,
what is going to be endured by an occupant ejecting using this system?
John
|
304.37 | They usually do. | ONEDGE::REITH | Jim Reith DTN 291-0072 - PDM1-1/J9 | Tue Mar 27 1990 09:39 | 6 |
| This isn't the normal egress method for good reason. The general feeling is that
the seat occupant needs to get away as quickly as possible or be killed. Pilots
are generally knocked out by the forces and banged around. Bones get broken but
in general it improves the chances of survival. The other choice is to stay with
the craft to whatever end. Challenger pointed out what that means. The fortunate
part is that the seat occupant has no active role after "punching out".
|
304.38 | Ejection Seat Acceleration | VOSTOK::LEPAGE | Life is a tale told by an idiot | Tue Mar 27 1990 11:25 | 7 |
| Re:.36
500 meters in 2 seconds would yeild an average acceleration of
250 m/s/s or about 25 Gs. It certainly would not be a pleasant
experience but it is better than the alternative!
Drew
|
304.39 | throw them backwards | SUBSYS::DOUCETTE | Jim Doucette | Tue Mar 27 1990 23:44 | 6 |
| It doesn't have to be 25 Gs. If the crew is ejected in the opposite
direction of the spaceplane, or with some vector in the opposite
direction, then the vehicle's forward motion would contribute some,
if not much, of the 500 meter distance in 2 seconds.
jim
|
304.40 | physics; ejection psychology | SAUTER::SAUTER | John Sauter | Wed Mar 28 1990 09:52 | 17 |
| re: .39
I think that's true only if the vehicle is still accelerating, a
dubious assumption. If it isn't accelerating then a crew member
ejected at 0G (to choose an easily-visualized case) will continue
to accompany the vehicle.
I am reminded of stories of a high-risk "bail out" feature in a world
war II plane. I think the position involved was the tail gunner's,
and I don't remember the name of the plane at all. According to the
story, the only way to eject from that position was downward through
the skin (some problem with the tail prevented ejecting upward). Under
operational conditions, according to the story, no crew member made
a successful ejection. ("Successful" means he lived to tell about it.)
Nevertheless, there were several attempts. I wonder of this ejection
system might turn out to be in the same category.
John Sauter
|
304.41 | Everything is relative! | DECWIN::FISHER | Prune Juice: A Warrior's Drink! | Wed Mar 28 1990 09:58 | 12 |
| Ah, sorry, Jim, but motion is relative. If the original cockpit is moving
forward at 250 meter/sec then the ejectee still has to accelerate in the
opposite direction by the same amount. Think of it this way: if you jump
out of a car going 50 mph, you decelerate (colloquial term for accelerate in the
opposite direction) very quickly when you hit the road.
So regardless of the initial velocity, the ejectee still has to accelerate at
250 meter/sec�, or about 25 Gs to get 500 meters away in 2 seconds. This is
assuming constant acceleration. If the initial burst were higher, the remainder
of the time could be lower.
Burns
|
304.42 | | DECWIN::FISHER | Prune Juice: A Warrior's Drink! | Wed Mar 28 1990 18:37 | 7 |
| I heard a story from an eyewitness about a downward-ejecting seat. It could
have been a B52, but I'm not too clear on that. It seems that some work was
being done in the circuitry and somehow the safety "on the ground" interlock
was disabled. Then someone managed to eject while the plane was on the
runway. Not a pretty sight. It left a big hole.
Burns
|
304.43 | Gruesome | IAMOK::ALLEGREZZA | George Allegrezza @VRO | Thu Mar 29 1990 09:53 | 5 |
| Early models of the Lockheed F-104 "Lieutenant Eater" had a
downward-firing ejection seat, designed to prevent a pilot from
striking the empennage during as high-speed ejection. Unfortunately,
as most ejections occur at low altitude (i.e. takeoff and landing),
this arrangement was less than optimal.
|
304.44 | why | PARITY::BIRO | | Thu Mar 29 1990 10:37 | 17 |
| yes in Rotc they show us a film of a f-104 with a flameout
on take off and he tried to eject, they now tell you if you
get a flame out on take off in a F-104 do a roll over...sure...
But on a shuttle mounted to a booster it has to be a upward-firing
ejection seat, but I guess if you don't use a booster you can go
many different ways. I wonder if other enginering considerations
were used, ie the placement of the heat shields, the effectiveness
of ejecting withing the first few seconds etc. Is there an Engineering
benifit or it is just what you can buy.... or worse yet a political
problem...
I think then in the French Air Show the Soviets showed there plan
carring the Hotel....
john
|
304.45 | F104 reason | PARITY::BIRO | | Thu Mar 29 1990 10:44 | 6 |
| Forgot the reason the ROTC gave on the F-104 downward-friing ejcection
seat was the fact of the high tail with it razor sharp edges. They
had problems clearing it at supersonic bailout.
jb
|
304.46 | 25G's??? | TUNER::FLIS | come to me... | Fri Mar 30 1990 17:36 | 5 |
| I always thought that 25G's would be beyond the limit of what a person
can withstand. Isn't it fatal?
jim
|
304.47 | F104 bailout | ECADSR::KINZELMAN | Paul Kinzelman | Fri Mar 30 1990 17:45 | 7 |
| Re: .43, etc., F104 bailout
From F-104 ex-jocky in the flying notes file...
The seat went down because the designers didn't feel that they had the
technology to make *any* ejection survivable at low altitude at the time,
therefore it was to be used only at high altitude and downward would be just
fine. Later, technology improved to make low-altitude ejection safe, and
then the downward ejection became a problem.
|
304.48 | | USMRM3::SPOPKES | | Fri Mar 30 1990 18:47 | 4 |
| At 25 g's, a 150 pound man would experience something like a "weight"
in excess of 3000 pounds. I'm not convinced this is livable.
steve p
|
304.49 | It may be possible - wouldn't try it standing up... | ANVIL::BUEHLER | Art is Science elevated | Sat Mar 31 1990 20:58 | 5 |
| Modern fighter pilots can sustain 9 G's with pressure suit and special
training for short periods (10 seconds or so). Instantaneous G's well above
this have been experienced in tests for much shorter periods (a second).
John
|
304.50 | I bet Stapp took 25 Gs | DECWIN::FISHER | Prune Juice: A Warrior's Drink! | Mon Apr 02 1990 17:53 | 6 |
| What is Col. Stapp's G record? I think it is in in the 20's, and it still holds,
so far as I know. (No one else crazy enough to try to break it, or else no one
could take the political heat of endangering even a volunteer like the did with
Stapp in the 50s.)
Burns
|
304.51 | t least you feel like you have a chance/choice | ONEDGE::REITH | Jim Reith DTN 291-0072 - PDM1-1/J9 | Mon Apr 02 1990 18:12 | 4 |
| The idea is to improve the survival chances. Get away so that the medics have a
broken but repairable body to work on ;^)
In many cases a 10% survival rate is better than staying with the plane.A
|
304.52 | Col. Stapp's G Record | LHOTSE::DAHL | Tom Dahl, CDMS | Tue Apr 03 1990 14:55 | 4 |
| RE: <<< Note 304.50 by DECWIN::FISHER "Prune Juice: A Warrior's Drink!" >>>
Stapp experienced 86 G's for a very brief period (something like .004 second).
-- Tom
|
304.53 | Not recommended for cardiovascular health | CURIE::HARRIS | En attendant Go..eh, le printemps | Tue Apr 03 1990 15:57 | 4 |
| Ho-kay, whatever happened to Colonel Stapp? Is he still with us? And
if not, wny not?
Mac.
|
304.54 | | DECWIN::FISHER | Prune Juice: A Warrior's Drink! | Tue Apr 03 1990 16:28 | 3 |
| If he's dead, it was not because of the acceleration experiement.
Burns
|
304.55 | | SARAH::DAHL | Tom Dahl, CDMS | Wed Apr 04 1990 00:14 | 4 |
| I recall that he was kept in a hospital for three days after the sled run for
observation, and that no lasting harmful effect was found that was attributed
to the experience.
-- Tom
|
304.56 | Soviets to help revive HOTOL? | ADVAX::KLAES | All the Universe, or nothing! | Mon Nov 19 1990 11:14 | 24 |
| From: [email protected] (Henry Spencer)
Newsgroups: sci.space,sci.space.shuttle
Subject: Space news from September 10 AW&ST etc.
Date: 19 Nov 90 03:59:15 GMT
Organization: U of Toronto Zoology
Heavyweight aircraft of the month: British Aerospace and the
Soviet Ministry of Aviation Industry propose reviving Hotol [!], using
an Antonov Mriya to carry a rocket-powered version of Hotol aloft,
avoiding the need for an advanced airbreathing engine. Estimated
payload to a low near-equatorial orbit is 7 tons, and costs are
estimated to be about $2000/kg, roughly a third of that for Ariane 5.
Re-engining Mriya with Rolls-Royce engines is being kept as a reserve
possibility against the chance that Hotol will gain weight in
development. The Soviets are investigating the carry and separation
aspects, and also the possibility of using Soviet oxyhydrogen engines
in Hotol. BA is looking into the modified Hotol, plus support and
economics. Both sides consider it promising, and estimate an
operational date circa 2000 if all goes well and funding (perhaps
$4.6G) can be found.
--
"I don't *want* to be normal!" | Henry Spencer at U of Toronto Zoology
"Not to worry." | [email protected] utzoo!henry
|
304.57 | Well, at least it will fly sometime | 42653::HAZEL | Author of Public Domain notes | Thu Nov 22 1990 08:34 | 11 |
| Re. .56:
I thought the advanced air-breathing engine had already been developed
by Rolls-Royce? Why would they want to avoid needing something which
was already developed?
If we didn't have all those bean counters here in the UK, this thing
would be nearly operational by now.
Dave Hazel
|
304.58 | We probably won't be on it though 8*( | 42110::RICKETTS | Have you tried kicking it? | Fri Nov 23 1990 03:16 | 21 |
| re. .57
I think that most of the preliminary design work has been done on
this engine, but that is about it; the thing is barely out of
the 'concept' stage. It's possible that a simple, small-scale model
has been built for wind tunnel testing, but I haven't heard about
it if one has. Has anyone even attempted to construct any sort of
full size prototype? Without that, such a new engine can hardly be
called 'developed'.
Remember, this is part of the 'Hotol' project. British Aerospace
and others have been funding this themselves so far, as the government
is simply not interested. I think they have spent about �3M so far,
and want government backing before they commit themselves to more.
That sort of money doesn't buy you very much from the modern aerospace
industry.
I agree about the bean counters. 8*(
Ken
|
304.59 | Interim HOTOL Project | VERGA::KLAES | All the Universe, or nothing! | Wed Jun 03 1992 21:57 | 62 |
| Article: 1092
From: [email protected] (Ian Taylor)
Newsgroups: sci.space.news
Subject: Project Interim Hotol
Date: 27 May 92 18:39:43 GMT
Sender: [email protected]
Organization: Alcatel Austria - Elin Research Center, Vienna
The recently published Space Technology International 1992 by Cornhill
Publications contains an intersting update on the `Interim Hotol'
project written by Dr Robert Parkinson of British Aerospace (BA).
Abstract:
Interim Hotol is joint BA/Soviet Ministry of Aviation {sic} study into
the use of an Antonov An-225 Myria heavy lift aircraft to carry the
Hotol reusable orbiter.
The Central Aero and Hydrodynamics Institute (TsAGI) near Moscow took
technical responsibility and used the Molnyia Design Bureau (of Buran
fame) for system studies. The Chemical Automatics Design Bureau
(responsible for the RD-0120 Energia second stage engine) assisted
with the Hotol main engine design.
Orbiter concept:
4 hydrogen-oxygen engines
`small' delta wing
integral payload bay
total all up mass 250 tonnes
Operations:
300km easterly orbit with 5-8 tonnes payload
launch costs US$12m {$1090 per lb}
24 flights per year
No operational date or development costs given :-(
Launch profile:
takes off piggy back on modified An-225 (two extra Lotarev D-18 engines)
requiring a 3000m runway for equatorial operations
40 minutes to climb to 9,400m
at release-60 sec An-225 enters shallow dive to mach 0.8
at release-15 sec An-225 rotates to slightly nose-up while descending
orbiter main engine ignition sequence started
at release main engines started
release+4 sec lower engine pair started
orbiter should move vertically upwards wrt An-225 {exciting stuff eh?}
ESTEC completed extended technical review in September 1991, next step
is to establish joint European technology program to validate study.
{pending death of Hermes?}.
Activities continue at BA and TsAGI.
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