Ada Success Story II

Ada Success Story II

[Ken Garlington]

rlove@raptor.neosoft.com (Robert B. Love) wrote:

<< With people so quick to blame Ada for the loss of Ariane I'd
like to point out that Saturday's Titan 4B flew with a new
flight computer programmed in Ada.  While I'm sketchy on details
they used a 1750 computer on a 1553 bus.  An old combination
of hardware but new for the Titan family.

Anybody from LockMart care to comment? >>

----------------------------------------------------------------

I can't comment on the Titan 4B, since it's not my division.
There may be a press release available on www.lmco.com in the
near future providing more details on the launch.

Speaking of press releases, here's another Ada success story in
the works from _my_ division of Lockheed Martin:

----------------------------------------------------------------

This information has been provided to the news media, with USAF
approval.  It refers to the initial software release in December; an
updated software package has since been released.

F-22 FIRST FLIGHT SOFTWARE PROGRAM COMPLETED

FORT WORTH, Texas -- Lockheed Martin Tactical Aircraft Systems recently
released the first complete Operational Flight Program (OFP) for the
F-22 aircraft.  The software package was electronically transmitted via
a secure communication link to Lockheed Martin Aeronautical Systems in
Marietta, Ga., where the F-22 is undergoing final assembly.
	The delivered OFP includes the computing power to control the major
subsystems needed for the first flight of the aircraft, including the
hydraulics and electrical power systems, flight controls, cockpit
displays and engine controls.   Elements of the software have been
developed by Lockheed Martin Tactical Aircraft Systems, Lockheed Martin
Aeronautical Systems and Boeing Military Airplanes Division.
	Lockheed Martin Tactical Aircraft Systems, Fort Worth, Tex., is
responsible for system testing and integration of the OFP for the
initial aircraft.  The initial software release includes 275,000 lines
of software code, of which Tactical Aircraft Systems developed about 57
percent.  An additional 1,450,000 lines of code will be developed during
Engineering and Manufacturing Development of the advanced avionics
systems for the F-22.
	The flyable software developed by F-22 team members and major suppliers
is integrated at Fort Worth and assembled into a single OFP for the
initial aircraft.  The OFP is loaded on the aircraft at the Marietta
site using a Portable Maintenance Aid (PMA) that was developed by
Lockheed Martin Tactical Aircraft Systems and Allied Signal.   	
	"The OFP assembly and load processes, demonstrated with this initial
release, encompass a significant advancement in software supportability
that will be used throughout the F-22 EMD, production, and field support
phases," said Charla K. Wise, F-22 vice president and program director
at Tactical Aircraft Systems.
	"The concept improves software reliability and maintainability,
simplifies the software update process, and will reduce life cycle cost
for the customer," Wise said.   "The quality and integrity of the total
software package is key to the success of any new fighter aircraft
flight- test program.  We are encouraged that major milestones in F-22
software development are occurring on schedule with no unforeseen
problems."
	Lockheed Martin Aeronautical Systems used the initial OFP release for
power-on testing of the first F-22 EMD aircraft.  Two additional
software releases are scheduled prior to the first flight of the F-22 in
May, to incorporate changes recommended as a result of the integration
testing at Fort Worth.
	The F-22 is being developed as the new air dominance fighter for the
U.S. Air Force.
			# # #

Re: Ada Success Story II

[Dale Pontius]

In article <3315C9E8.72D8@lmtas.lmco.com>,
        Ken Garlington <GarlingtonKE@lmtas.lmco.com> writes:
>
> I can't comment on the Titan 4B, since it's not my division.
> There may be a press release available on www.lmco.com in the
> near future providing more details on the launch.
>
> Speaking of press releases, here's another Ada success story in
> the works from _my_ division of Lockheed Martin:
>
Too bad the press release doesn't mention Ada, just that they
felt it was a successful development cycle. Of course the proof
is in the flying.

There was a flyoff between the YF22 and the YF23, which the YF22
won. What were they doing for flight software on the flyoff? I
could believe hacked F16 software, or something like that, except
isn't the F22 the first plane to use thrust vectoring?

It seems about time for CJIII to jump in, with these Ada success
stories showing up. (for rebuttal, of course)

Dale Pontius
(NOT speaking for IBM)

Re: Ada Success Story II

[Larry Kilgallen]

In article <5f4d06$1644@mdnews.btv.ibm.com>, pontius@btv.vnet.ibm.com (Dale Pontius) writes:

> It seems about time for CJIII to jump in, with these Ada success
> stories showing up. (for rebuttal, of course)
> 
> Dale Pontius
> (NOT speaking for IBM)

Ok, so we won't blame the IBM Corporation for tempting fate.

Re: Ada Success Story II

[Dale Pontius]

In article <1997Feb27.133008.1@eisner>,
        kilgallen@eisner.decus.org (Larry Kilgallen) writes:
> In article <5f4d06$1644@mdnews.btv.ibm.com>, pontius@btv.vnet.ibm.com (Dale Pontius) writes:
>
>> It seems about time for CJIII to jump in, with these Ada success
>> stories showing up. (for rebuttal, of course)
>>
>> Dale Pontius
>> (NOT speaking for IBM)
>
> Ok, so we won't blame the IBM Corporation for tempting fate.

Naah! I guess I should take the blame, personally. Hoooo Boy!

Dale Pontius
(still NOT speaking for IBM)

Re: Ada Success Story II

[Marin David Condic, 561.796.8997, M/S 731-93]

Dale Pontius <pontius@BTV.VNET.IBM.COM> writes:
>There was a flyoff between the YF22 and the YF23, which the YF22
>won. What were they doing for flight software on the flyoff? I
>could believe hacked F16 software, or something like that, except
>isn't the F22 the first plane to use thrust vectoring?
>
    For the record, the Pratt engines used in both the YF22 & YF23 had
    engine controls programmed in Ada. The contract officer overseeing
    our development efforts looked at how we develop control software
    in Ada and pronounced himself "suitably whelmed" and in commenting
    on our use of Ada said words to the effect of: "to think, I had to
    see it from an *engine* company" (as opposed to an avionics
    company, most of whom were staying away from Ada in droves.)

    The F22 is not the first plane to use thrust vectoring. There were
    a number of research programs that mounted thrust vectoring
    nozzles on things like the F15. We've even built a 3-D nozzle for
    the F100 engines used by F15s and F16s - nicknamed "the eyeball"
    because of it's ability to swivel around and open&close much like
    the pupil of an eye. The Harrier most certainly does thrust
    vectoring. And if one would want to pick a few nits, the
    commercial airliners have been using thrust vectoring (thrust
    reversers) long before the Air Force was willing to take a chance
    on such technology.

    Still, it's pretty cool to watch them test the F119 engine and
    have it pull its thrust vectoring tricks on the stand. There's a
    lot of technological advancement in this particular engine.

    MDC

Marin David Condic, Senior Computer Engineer    ATT:        561.796.8997
M/S 731-96                                      Technet:    796.8997
Pratt & Whitney, GESP                           Fax:        561.796.4669
P.O. Box 109600                                 Internet:   CONDICMA@PWFL.COM
West Palm Beach, FL 33410-9600                  Internet:   CONDIC@FLINET.COM
===============================================================================
    "Airplanes are interesting toys but of no military value."

        --  Marechal Ferdinand Foch, Professor of Strategy, Ecole Superieure
            de Guerre.
===============================================================================

Re: Ada Success Story II

[Jon S Anthony]

In article <97030217543582@psavax.pwfl.com> "Marin David Condic, 561.796.8997, M/S 731-93" <condicma@PWFL.COM> writes:

>     The F22 is not the first plane to use thrust vectoring. There were
>     a number of research programs that mounted thrust vectoring
>     nozzles on things like the F15. We've even built a 3-D nozzle for
>     the F100 engines used by F15s and F16s - nicknamed "the eyeball"

Are these the engines that are to go on the "F15X"?  My understanding
was that this was going to be an actual production version.  Yes?  No?

/Jon
-- 
Jon Anthony
Organon Motives, Inc.
Belmont, MA 02178
617.484.3383
jsa@organon.com

Re: Ada Success Story II

[Robert S. White]

In article <97030217543582@psavax.pwfl.com>, condicma@PWFL.COM says...
	...snip...

>    on our use of Ada said words to the effect of: "to think, I had to
>    see it from an *engine* company" (as opposed to an avionics
>    company, most of whom were staying away from Ada in droves.)

	...snip...

	Ow!  Unfair! ;-) Rockwell Collins has been using Ada for new 
avionics since the mid 80's (MIL-STD-1815A).  Sure there are some legacy 
products continuously maintained since the 70's for older aircraft that use 
older languages (ever hear of AED?). Before 1984 the old NY Ada-Ed compiler 
was used (plain MIL-STD-1815) for training purposes.
_______________________________________________________________________
Robert S. White                    -- an embedded sys software engineer
				   -- speaking for myself from memories

Re: Ada Success Story II

[Jon S Anthony]

In article <97030510245774@psavax.pwfl.com> "Marin David Condic, 561.796.8997, M/S 731-93" <condicma@PWFL.COM> writes:

>     never designed with the intent of utilizing the nozzle. Ultimately
>     - if the nozzles do what you'd like - you'd be able to remove all
>     the control surfaces off the back of the airplane.

Speaking as an acro pilot, this sounds mighty scary!  Would this sort
of thing really offer the sort of control capability to get you out of
spins and such?  Hmmm, OTOH, spinning a jet is pretty much going to
kill it anyway, so maybe this is simply irrlevant...


>     I'm afraid that I don't know anything about the "F15X" (some
>     experiment being done by McDonnel Douglas?) at the moment.
>     Anything you can tell me about it so I could find out who to ask?
>     There might be some interesting control work being done there.

Well, I don't know much about it either.  I can't recall where I heard
about it - Aviation Leak or some related rag.  Supposedly, the idea
_is_ to retro fit some thrust vectoring version onto some version of
some set of F15 airframes.  How's that for hedging? ;-) It may be
these were going to be "new" airframes where the design will have been
twiddled in some ways to be more accommodating.  But really - I don't
know.

/Jon

-- 
Jon Anthony
Organon Motives, Inc.
Belmont, MA 02178
617.484.3383
jsa@organon.com

Re: Ada Success Story II

[Marin David Condic, 561.796.8997, M/S 731-93]

Jon S Anthony <jsa@ALEXANDRIA.AMERICAN.EDU> writes:
>>     The F22 is not the first plane to use thrust vectoring. There were
>>     a number of research programs that mounted thrust vectoring
>>     nozzles on things like the F15. We've even built a 3-D nozzle for
>>     the F100 engines used by F15s and F16s - nicknamed "the eyeball"
>
>Are these the engines that are to go on the "F15X"?  My understanding
>was that this was going to be an actual production version.  Yes?  No?
>
    There might probably be some plans to retrofit some subset of the
    existing fleet with "production" thrust vectoring nozzles, but I
    am personally unaware of any such activity or operation...

    What we've mostly done is build "technology demonstrators" which
    someone will take and mount on the back end of an available plane
    and fly it around to see if it works the way you thought it
    should. We usually do that research in order to better design a
    future engine.

    It's pretty costly to retrofit some existing airframe and you may
    not get all the performance you'd expect because the airframe was
    never designed with the intent of utilizing the nozzle. Ultimately
    - if the nozzles do what you'd like - you'd be able to remove all
    the control surfaces off the back of the airplane.

    I'm afraid that I don't know anything about the "F15X" (some
    experiment being done by McDonnel Douglas?) at the moment.
    Anything you can tell me about it so I could find out who to ask?
    There might be some interesting control work being done there.

    MDC

Marin David Condic, Senior Computer Engineer    ATT:        561.796.8997
M/S 731-96                                      Technet:    796.8997
Pratt & Whitney, GESP                           Fax:        561.796.4669
P.O. Box 109600                                 Internet:   CONDICMA@PWFL.COM
West Palm Beach, FL 33410-9600                  Internet:   CONDIC@FLINET.COM
===============================================================================
    "Eagles may soar, but a weasle never gets sucked up into a jet
    engine."

        --  Author Unknown
===============================================================================

Re: Ada Success Story II

[Peter Amey]

> Jon S Anthony <jsa@ALEXANDRIA.AMERICAN.EDU> writes:
> >>     The F22 is not the first plane to use thrust vectoring. There were
> >>     a number of research programs that mounted thrust vectoring
> >>     nozzles on things like the F15. We've even built a 3-D nozzle for
> >>     the F100 engines used by F15s and F16s - nicknamed "the eyeball"

I missed the beginning of this thread but can't resist mentioning the
British Aerospace Harrier (aka the McDonnell Douglas Harrier) when "thrust
vectoring" is mentioned! 

Peter

Re: Ada Success Story II

[Ender]

In article <3315C9E8.72D8@lmtas.lmco.com>,
	Ken Garlington <GarlingtonKE@lmtas.lmco.com> writes:
> rlove@raptor.neosoft.com (Robert B. Love) wrote:
> 
> << With people so quick to blame Ada for the loss of Ariane I'd
> like to point out that Saturday's Titan 4B flew with a new
> flight computer programmed in Ada.  While I'm sketchy on details
> they used a 1750 computer on a 1553 bus.  An old combination
> of hardware but new for the Titan family.
> 
> Anybody from LockMart care to comment? >>
> 
Well, I'm not commenting for LockMart (great name though :-)  I do Ada for
another LM division, but my system is quite land-based. Though it might be 
preaching to the choir here, I really have to point out that the Ariane 
failure was in no way related to Ada (or any language) but rather a PROCESS 
failure. Nobody documented the "shortcut" taken (no exception handler), so 
nobody knew it wouldn't work in other flight regimes, so nobody tested it, 
so the rocket blew up.  Kind of a graphic demonstration of the "hidden" 
costs of software engineering shortcuts, eh?

Just my $0.0122 ($@&!^@ withholding taxes)


-------------------------------------------------------------
Chris Curtis          UNIX is user-friendly; it's just     
ender@aros.net        selective about who its friends are  
Team Ada              http://www.aros.net/~ender/

Re: Ada Success Story II

[Rob Wells]

Jon S Anthony wrote:
> 
> In article <97030510245774@psavax.pwfl.com> "Marin David Condic, 561.796.8997, M/S 731-93" <condicma@PWFL.COM> writes:
> 
> >     never designed with the intent of utilizing the nozzle. Ultimately
> >     - if the nozzles do what you'd like - you'd be able to remove all
> >     the control surfaces off the back of the airplane.
> 
> Speaking as an acro pilot, this sounds mighty scary!  Would this sort
> of thing really offer the sort of control capability to get you out of
> spins and such?  Hmmm, OTOH, spinning a jet is pretty much going to
> kill it anyway, so maybe this is simply irrlevant...

I seem to remember that there was a MD-11(?) that was tested at NASA
Dryden which actually used this principle. There are photos of it (along
with several other thrust vectoring research A/C) over at

http://www.dfrf.nasa.gov/dryden.html

Rob W. (-:

<snip>

Re: Ada Success Story II

[Larry J. Elmore]

Jon S Anthony <jsa@alexandria> wrote in article
<JSA.97Mar5183223@alexandria>...
> In article <97030510245774@psavax.pwfl.com> "Marin David Condic,
561.796.8997, M/S 731-93" <condicma@PWFL.COM> writes:
> 
> >     never designed with the intent of utilizing the nozzle. Ultimately
> >     - if the nozzles do what you'd like - you'd be able to remove all
> >     the control surfaces off the back of the airplane.
> 
> Speaking as an acro pilot, this sounds mighty scary!  Would this sort
> of thing really offer the sort of control capability to get you out of
> spins and such?  Hmmm, OTOH, spinning a jet is pretty much going to
> kill it anyway, so maybe this is simply irrlevant...

There's a number of planes flying now, such as the X-29, that are
inherently unstable in flight and require continuous monitoring and flight
control adjustments by their computer control systems. This is a highly
desirable feature in a fighter plane (makes it very maneuverable as
compared to safe, stable planes), but until now there was a limit on how
far one could take that before the plane was unflyable. As it was, some of
the most successful fighters of the past had horrendously high accident
rates with student pilots. I suppose one could do away with some of the
control surfaces on planes with vectoring nozzles, but I just don't see it
happening in the real world. What happens if your engine flames out? You'd
probably have no chance to attempt to relight it, you'd just have to punch
out immediately. I suspect thrust vectoring would work best in conjunction
with control surfaces on a plane specifically designed for it. 

> >     I'm afraid that I don't know anything about the "F15X" (some
> >     experiment being done by McDonnel Douglas?) at the moment.
> >     Anything you can tell me about it so I could find out who to ask?
> >     There might be some interesting control work being done there.
> 
> Well, I don't know much about it either.  I can't recall where I heard
> about it - Aviation Leak or some related rag.  Supposedly, the idea
> _is_ to retro fit some thrust vectoring version onto some version of
> some set of F15 airframes.  How's that for hedging? ;-) It may be
> these were going to be "new" airframes where the design will have been
> twiddled in some ways to be more accommodating.  But really - I don't
> know.

I think the F-15X has only 2-D vectoring (vertical). Anyone know if Ada was
used for the X-29 avionics?

-- 
-----------------------------------------------------
Larry J. Elmore
Bozeman, Montana

"And they shall beat their swords into plowshares."
--Isaiah 2:4

"History teaches us that those who beat their swords into plowshares
usually end up plowing for those who kept their swords."
--Anon.

Re: Ada Success Story II

[Mike Stark]

Larry J. Elmore wrote:
> 
<much interesting stuff on dynamically unstable aircraft deleted>
> 
> I think the F-15X has only 2-D vectoring (vertical). Anyone know if Ada was
> used for the X-29 avionics?

I doubt that Ada was used for the X-29, since it flew in the mid-80s
somewhere (I think 1st flight was in 1984, but I don't have any of my
aircraft books here at work).
> 
> --
> -----------------------------------------------------
> Larry J. Elmore
> Bozeman, Montana
> 
> "And they shall beat their swords into plowshares."
> --Isaiah 2:4
> 
> "History teaches us that those who beat their swords into plowshares
> usually end up plowing for those who kept their swords."
> --Anon.

Re: Ada Success Story II

[Mike Stark]

Rob Wells wrote:
> 
> Jon S Anthony wrote:
> >
> > In article <97030510245774@psavax.pwfl.com> "Marin David Condic, 561.796.8997, M/S 731-93" <condicma@PWFL.COM> writes:
> >
> > >     never designed with the intent of utilizing the nozzle. Ultimately
> > >     - if the nozzles do what you'd like - you'd be able to remove all
> > >     the control surfaces off the back of the airplane.
> >
> > Speaking as an acro pilot, this sounds mighty scary!  Would this sort
> > of thing really offer the sort of control capability to get you out of
> > spins and such?  Hmmm, OTOH, spinning a jet is pretty much going to
> > kill it anyway, so maybe this is simply irrlevant...
> 
> I seem to remember that there was a MD-11(?) that was tested at NASA
> Dryden which actually used this principle. There are photos of it (along
> with several other thrust vectoring research A/C) over at
> 
> http://www.dfrf.nasa.gov/dryden.html
> 
> Rob W. (-:
> 
> <snip>

And follow the link to the Propulsion Controlled Aircraft research from
Dryden's home
page, or if you are not particularly interested in their other research,
you can go
directly to

http://www.dfrf.nasa.gov/Projects/PCA/index.html

This experiment isn't really using thrust vectoring in the sense of
rotating nozzles --
it is using differential power settings on twin-engine aircraft to
maneuver.  This was
originally tried manually by the pilots in the Sioux City crash a few
years back, and
was partially successful in that the pilot landed and there were
survivors.  The Dryden
Web site describes how an a control system was developed, then tested
first on an F-15
simulator, then an F-15, then an MD-11.  Anyway, it is truly an
interesting research
project from which the taxpayer will get a bargain the first time this
system works to
avert a crash!

Mike

Re: Ada Success Story II

[Jon S Anthony]

In article <01bc29a4$11a606c0$5e6700cf@default> "Larry J. Elmore" <ljelmore@montana.campus.mci.net> writes:

Well, we have definitely strayed off subject area here, but one
final comment...

> Jon S Anthony <jsa@alexandria> wrote in article
> <JSA.97Mar5183223@alexandria>...
> > In article <97030510245774@psavax.pwfl.com> "Marin David Condic,
> 561.796.8997, M/S 731-93" <condicma@PWFL.COM> writes:
> > 
> > >     never designed with the intent of utilizing the nozzle. Ultimately
> > >     - if the nozzles do what you'd like - you'd be able to remove all
> > >     the control surfaces off the back of the airplane.
> > 
> > Speaking as an acro pilot, this sounds mighty scary!  Would this sort
> > of thing really offer the sort of control capability to get you out of
> > spins and such?  Hmmm, OTOH, spinning a jet is pretty much going to
> > kill it anyway, so maybe this is simply irrlevant...
> 
> There's a number of planes flying now, such as the X-29, that are
> inherently unstable in flight and require continuous monitoring and flight
> control adjustments by their computer control systems. This is a highly
> desirable feature in a fighter plane (makes it very maneuverable as
> compared to safe, stable planes),

Right.  Actually, acro ships are pretty unstable.  Ever fly a Pitts or
Extra?  They're not so wild as to _require_ computer control like the
X-29 or EFA (outside of a GPS and a COM, there's not much electronics,
period), but they do require constant attention.  Fade out for a
second and the things will just take off on ya.


> I suppose one could do away with some of the control surfaces on
> planes with vectoring nozzles, but I just don't see it happening in
> the real world. What happens if your engine flames out? You'd
> probably have no chance to attempt to relight it, you'd just have to
> punch out immediately. I suspect thrust vectoring would work best in
> conjunction with control surfaces on a plane specifically designed
> for it.

This seems right to me too.  BTW, even punching out would probably not
be under your control.  My understanding is that the EFA is so
unstable that any control loss would be so violent and disorienting
that you would not be quick enough to punch out on your own.

> I think the F-15X has only 2-D vectoring (vertical).

That's my understanding as well.

> Anyone know if Ada was used for the X-29 avionics?

Wow, an Ada relevant comment! :-)


/Jon
-- 
Jon Anthony
Organon Motives, Inc.
Belmont, MA 02178
617.484.3383
jsa@organon.com

Re: Ada Success Story II

[Ken Garlington]

Marin David Condic, 561.796.8997, M/S 731-93 wrote:
> 
> Dale Pontius <pontius@BTV.VNET.IBM.COM> writes:
> >There was a flyoff between the YF22 and the YF23, which the YF22
> >won. What were they doing for flight software on the flyoff? I
> >could believe hacked F16 software, or something like that, except
> >isn't the F22 the first plane to use thrust vectoring?
> >
>     For the record, the Pratt engines used in both the YF22 & YF23 had
>     engine controls programmed in Ada. The contract officer overseeing
>     our development efforts looked at how we develop control software
>     in Ada and pronounced himself "suitably whelmed" and in commenting
>     on our use of Ada said words to the effect of: "to think, I had to
>     see it from an *engine* company" (as opposed to an avionics
>     company, most of whom were staying away from Ada in droves.)

The YF-22 flight control system, which was coupled with the Pratt (and
GE)
engines to make the integrated flight propulsion system, was also
programmed
in Ada using the TeleSoft VAX/1750 toolset. This software was developed
by General
Dynamics Fort Worth Division (now Lockheed Martin Tactical Aircraft
Systems).
The YF-22 flight control software design was an evolutionary product,
based on our work
on the AFTI/F-16 and F-16 digital flight control systems. See:

  Garlington, K. and Tyrrell, A. "A Case Study: F-16 Ada Digital Flight
Control
  System," AIAA/IEEE 8th Digital Avionics Systems Conference, October
17-20, 1988

I never wrote a paper about the YF-22 flight control system. I might
write one 
about the F-22 flight controls at some point, but I'd like to get it
flying first :)

I have been told that the YF-23 flight control system was written in
JOVIAL. I can't
prove that our use of Ada (which wasn't required, by the way) helped us
win, but
it's a nice thought.

--
LMTAS - The Fighter Enterprise - "Our Brand Means Quality"
For job listings, other info: http://www.lmtas.com or
http://www.lmco.com

Re: Ada Success Story II

[JP Thornley]

In article: <JSA.97Mar7142555@alexandria>  jsa@alexandria (Jon S 
Anthony) writes:
>   My understanding is that the EFA is so
> unstable that any control loss would be so violent and disorienting
> that you would not be quick enough to punch out on your own.

Because of this there was an proposal for automatic eject in some
circumstances but the pilots refused absolutely to accept it.

And, to bring this back to topic, I guess EFA counts as a 
major Ada success story as well.

Phil Thornley

-- 
------------------------------------------------------------------------
| JP Thornley    EMail jpt@diphi.demon.co.uk                           |
------------------------------------------------------------------------

Re: Ada Success Story II

[Marin David Condic, 561.796.8997, M/S 731-93]

Jon S Anthony <jsa@ALEXANDRIA.AMERICAN.EDU> writes:
>> I suppose one could do away with some of the control surfaces on
>> planes with vectoring nozzles, but I just don't see it happening in
>> the real world. What happens if your engine flames out? You'd
>> probably have no chance to attempt to relight it, you'd just have to
>> punch out immediately. I suspect thrust vectoring would work best in
>> conjunction with control surfaces on a plane specifically designed
>> for it.
>
>This seems right to me too.  BTW, even punching out would probably not
>be under your control.  My understanding is that the EFA is so
>unstable that any control loss would be so violent and disorienting
>that you would not be quick enough to punch out on your own.
>
    Actually, nobody has any plans to remove the control surfaces from
    the tail of the plane any time soon. It's more of a long range
    goal which - if you prove out the technology of thrust vectoring -
    would be an atainable (and desirable) thing to do. (reduce drag,
    weight, etc.)

    Flame outs? Nobody is talking about doing this sort of thing on
    single engine craft just yet. *IF* it gets done, it would first be
    done on a dual engine craft similar to the F15 or F22. *IF* it
    worked successfully there and you started building enough
    confidence in the design (and in your Ada-programmed engine
    control's ability to keep the engine from stalling (had to get an
    Ada point in there ;-)) you might start designing a single engine
    craft around it.

    As for punching out of a mach-1 airplane that's gone unstable
    because the flight control went casters-up (Programmed in C?) -
    that sounds like a perfectly good way to ruin your whole day.
    There was a time when Aerospace Engineers didn't like fly-by-wire
    because they felt it wasn't reliable like their good, old, leaky
    hydraulics. And a time when hydraulics weren't considered as
    reliable as cables & pullies. Hence I think there will come a time
    when thrust vectoring nozzles will get enough trust to replace
    tail surfaces and pilots won't punch out of any more aircraft then
    than they do now because an actuator sticks & won't move the
    control surfaces.

    MDC

Marin David Condic, Senior Computer Engineer    ATT:        561.796.8997
M/S 731-96                                      Technet:    796.8997
Pratt & Whitney, GESP                           Fax:        561.796.4669
P.O. Box 109600                                 Internet:   CONDICMA@PWFL.COM
West Palm Beach, FL 33410-9600                  Internet:   CONDIC@FLINET.COM
===============================================================================
    "Eagles may soar, but a weasle never gets sucked up into a jet engine."

        --  Author Unknown
===============================================================================

Re: Ada Success Story II

[@ 1997-03-11 0:00 UTC (permalink / raw)]

"Marin David Condic, 561.796.8997, M/S 731-93" <condicma@PWFL.COM> wrote:

>     Actually, nobody has any plans to remove the control surfaces from
>     the tail of the plane any time soon. It's more of a long range
>     goal which - if you prove out the technology of thrust vectoring -
>     would be an atainable (and desirable) thing to do. (reduce drag,
>     weight, etc.)
Actually I think the goal is to remove not just the control surfaces
but the whole (vertical) tail (see X-36). 
The X-31 demonstrated pretty successfully that thrust vectoring is
indeed doable.

Does Anybody know if the X-31 autopilot was written in Ada ?
( Is anybody from  Daimler-Benz Aerospace reading this ? )

CU,

Ralph Paul

	ralph@ifr.luftfahrt.uni-stuttgart.de