Fly-By-Wire Flight Controls

[Charles Talleyrand]

Suppose a smaller airplane with it's fly-by-wire controls goes runs out
of fuel. All the engines quit. On a larger jet a ram air turbine
would drop into the airstream and power the controls. How does it work
on smaller planes like the Dassault Falcon or the F-16?

Alternatively, I've always wondered if one could not keep a special
reserve tank for the APU. When the engines quit, the APU
automatically starts to power the controls. Would such a system be
safe and would it be certifiable? Would it weigh less than the
existing system?

-Charles Talleyrand

"Charles Talleyrand" > wrote in message
oups.com...
> Suppose a smaller airplane with it's fly-by-wire controls goes runs out
> of fuel. All the engines quit. On a larger jet a ram air turbine
> would drop into the airstream and power the controls. How does it work
> on smaller planes like the Dassault Falcon or the F-16?
>
> Alternatively, I've always wondered if one could not keep a special
> reserve tank for the APU. When the engines quit, the APU
> automatically starts to power the controls. Would such a system be
> safe and would it be certifiable? Would it weigh less than the
> existing system?
>
> -Charles Talleyrand


On the A-6E and EA-6B aircraft, the Emergency Ram Air Turbine (RAT) only
powers the Emergency DC Bus which in turn provides power to a small set of
essential instruments. It does not provide any hydraulic power for the
flight controls.

[Eunometic]

Charles Talleyrand wrote:
> Suppose a smaller airplane with it's fly-by-wire controls goes runs out
> of fuel. All the engines quit. On a larger jet a ram air turbine
> would drop into the airstream and power the controls. How does it work
> on smaller planes like the Dassault Falcon or the F-16?

The same way on a BAE Hawk.
>
> Alternatively, I've always wondered if one could not keep a special
> reserve tank for the APU. When the engines quit, the APU
> automatically starts to power the controls. Would such a system be
> safe and would it be certifiable? Would it weigh less than the
> existing system?

Some years ago there was an Airbus A330 FBW fly by wire widebody that
ran out of fuel crossing the atlantic. It had to make an emergency
landing at (I thnk) the Azores I think from over 100km out without
fuel.

A leaking fuel delivery pipe in the engine pylon drained the aircrafts
fuel: the pilot didn't believe his instruments and thus kept
transfering fuel from the good side to the bad side rather than
shutdown the bad engine. He thus drained both wings.

When fuel cut out (I saw a dramatisation ogf the events) the ram air
turbine deployed and the pilots, after finally acknowledging their fuel
situation went through their checklist.

Lights and pressurisation was lost with the power.

Most pointedly they lost spoilers and flaps; they really only had a few
instruments, ailerons, tail surfaces and the undercarriage. As a
result of being without flaps the landing speed was very high and
becuase there were no spoilers they couldn't loose speed or altitude
and actually had to circle and zig zag to loose both speed an altitude.
This made the one chance of making the runway even harder as there
would be no go arounds.

To cap it all of the runway in the azores ends in a 300ft shear cliff.
They stopped a few dozen meters short with blown tyres.

Airbus changed their software and though the pilot was clearly not
making the best decisions that day it was easier to given him awards.

The ram air turbine provides very little power. I think the idea of
giving the APU its own reserve fuel supply is tempered by the fact that
it is perhaps better to keep the engine lit for a few seconds longer.

Perhaps a cartriedge or two of of rocket-gas generator turbine could be
used to provide pressure for flap and spoiler deployment

[[email protected]]

>Perhaps a cartriedge or two of of rocket-gas generator turbine could be
>used to provide pressure for flap and spoiler deployment

Why not just load more fuel. It would not weigh any more and would be
far less complicated. Also have sirens which screech at the pilot.

[Benjamin Gawert]

Charles Talleyrand schrieb:

> Suppose a smaller airplane with it's fly-by-wire controls goes runs out
> of fuel. All the engines quit. On a larger jet a ram air turbine
> would drop into the airstream and power the controls. How does it work
> on smaller planes like the Dassault Falcon or the F-16?

The Panavia 200 Tornado has a EPS battery (one shot battery) that in
case of double engine out situations supplies a few instruments and an
electric pump to have some hydraulic pressure. This allows maintaining
control over the a/c for ~5-7 (max 10) minutes.

> Alternatively, I've always wondered if one could not keep a special
> reserve tank for the APU. When the engines quit, the APU
> automatically starts to power the controls. Would such a system be
> safe and would it be certifiable? Would it weigh less than the
> existing system?

I a lot of airplanes the APUs (resp. their intakes and exhausts) are
mounted in a way that they can't be used inflight. Besides that, if
there still is fuel in the tanks it's better served for keeping the
engine alive than just the APU...

Benjamin

[Keith W]

"Eunometic" > wrote in message
ups.com...

>
> Some years ago there was an Airbus A330 FBW fly by wire widebody that
> ran out of fuel crossing the atlantic. It had to make an emergency
> landing at (I thnk) the Azores I think from over 100km out without
> fuel.
>

70nm at 34,500 ft

> A leaking fuel delivery pipe in the engine pylon drained the aircrafts
> fuel: the pilot didn't believe his instruments and thus kept
> transfering fuel from the good side to the bad side rather than
> shutdown the bad engine. He thus drained both wings.
>
> When fuel cut out (I saw a dramatisation ogf the events) the ram air
> turbine deployed and the pilots, after finally acknowledging their fuel
> situation went through their checklist.
>
> Lights and pressurisation was lost with the power.
>
> Most pointedly they lost spoilers and flaps; they really only had a few
> instruments, ailerons, tail surfaces and the undercarriage. As a
> result of being without flaps the landing speed was very high and
> becuase there were no spoilers they couldn't loose speed or altitude
> and actually had to circle and zig zag to loose both speed an altitude.
> This made the one chance of making the runway even harder as there
> would be no go arounds.
>
> To cap it all of the runway in the azores ends in a 300ft shear cliff.
> They stopped a few dozen meters short with blown tyres.
>
> Airbus changed their software and though the pilot was clearly not
> making the best decisions that day it was easier to given him awards.
>

Airbus did not change their software which had behaved correctly, they
re-issued the flight manuals emphasizing the advice that was already
present to close the cross feed valves in the case of unexpectedly high
fuel consumption on one engine.

Transport Canada fined the airline C$250,000 (about US$165,000)
for maintenance infractions relating to an improper installation of a
hydraulic pump on an engine of the incident aircraft.


Keith



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[Les Matheson]

The F-16 uses a Hydrazine/Platinum (IIRC) APU to generate electricity.

Les


"Charles Talleyrand" > wrote in message
oups.com...
> Suppose a smaller airplane with it's fly-by-wire controls goes runs out
> of fuel. All the engines quit. On a larger jet a ram air turbine
> would drop into the airstream and power the controls. How does it work
> on smaller planes like the Dassault Falcon or the F-16?
>
> Alternatively, I've always wondered if one could not keep a special
> reserve tank for the APU. When the engines quit, the APU
> automatically starts to power the controls. Would such a system be
> safe and would it be certifiable? Would it weigh less than the
> existing system?
>
> -Charles Talleyrand
>

[John Carrier]

Glide speed generally provides sufficient windmill RPM on the engine(s) to
provide sufficient hydraulic power so that the controls (they don't have to
be fly-by-wire, any irreversible hyd flight control system is effected) have
sufficient pressure and volume to operate normally with moderate control
inputs.

R / John

"Charles Talleyrand" > wrote in message
oups.com...
> Suppose a smaller airplane with it's fly-by-wire controls goes runs out
> of fuel. All the engines quit. On a larger jet a ram air turbine
> would drop into the airstream and power the controls. How does it work
> on smaller planes like the Dassault Falcon or the F-16?
>
> Alternatively, I've always wondered if one could not keep a special
> reserve tank for the APU. When the engines quit, the APU
> automatically starts to power the controls. Would such a system be
> safe and would it be certifiable? Would it weigh less than the
> existing system?
>
> -Charles Talleyrand
>

[Mu]

On 14 Dec 2005 22:43:21 -0800, "Charles Talleyrand"
> wrote:

>Suppose a smaller airplane with it's fly-by-wire controls goes runs out
>of fuel. All the engines quit. On a larger jet a ram air turbine
>would drop into the airstream and power the controls. How does it work
>on smaller planes like the Dassault Falcon or the F-16?
>

F16's have a EPU, and according to this link
http://www.f-16.net/f-16_forum_viewtopic-t-1056.html you've got
around 10 minutes in Hydrazine mode, to find a nice piece of concreet.
After those 10 minutes it's gonna be a membership of the Martin Baker
Fanclub.

greetz Mu

[Carl Orton]

"Mu" > wrote in message
...
> F16's have a EPU, and according to this link
> http://www.f-16.net/f-16_forum_viewtopic-t-1056.html you've got
> around 10 minutes in Hydrazine mode, to find a nice piece of concreet.
> After those 10 minutes it's gonna be a membership of the Martin Baker
> Fanclub.
Love the reference to Baker!!!

[Eunometic]

Benjamin Gawert wrote:
> Charles Talleyrand schrieb:
>
> > Suppose a smaller airplane with it's fly-by-wire controls goes runs out
> > of fuel. All the engines quit. On a larger jet a ram air turbine
> > would drop into the airstream and power the controls. How does it work
> > on smaller planes like the Dassault Falcon or the F-16?
>
> The Panavia 200 Tornado has a EPS battery (one shot battery) that in
> case of double engine out situations supplies a few instruments and an
> electric pump to have some hydraulic pressure. This allows maintaining
> control over the a/c for ~5-7 (max 10) minutes.

These EPS (Emergency Power System) Batteries are usually known as
"Thermal Batteries". They have an eutectic electrolyte of salts that
are melted by a pyrotechnical charge. Because the electrolyte is inert
and sold untill melted shelf lives of 20+ years are possible. Because
of the high opperating temperature very high power densities are
possible.

20 years would not be full life for an airliner and a ram air turbine I
suggest would require less maintenance. (ie it doesn't ever need
replacement)

Thermal batteries appear to be the battery of choice for missiles. I
did read though that the early MANPAD Stingers handed over to the
Mujahidine had thermal batteries that would now be failing and thus
(thankfully) rendering the missiles inopperational.

The Panavia Tornado also has Nickel Cadmium Secondary rechargeable
batteries (perhaps upgraded to NiMH now?) for APU starting and other
power. I suspect that these could keep the system up for a few minutes
on their own if in good condition.

>
> > Alternatively, I've always wondered if one could not keep a special
> > reserve tank for the APU. When the engines quit, the APU
> > automatically starts to power the controls. Would such a system be
> > safe and would it be certifiable? Would it weigh less than the
> > existing system?
>
> I a lot of airplanes the APUs (resp. their intakes and exhausts) are
> mounted in a way that they can't be used inflight.

This would hardly apply to the Tornado. Tornado however uses its
entire slab sided botton fueselage for weapons: there is little room
for ram air turbine.

Besides that, if
> there still is fuel in the tanks it's better served for keeping the
> engine alive than just the APU...
>
> Benjamin

[Eunometic]

Carl Orton wrote:
> "Mu" > wrote in message
> ...
> > F16's have a EPU, and according to this link
> > http://www.f-16.net/f-16_forum_viewtopic-t-1056.html you've got
> > around 10 minutes in Hydrazine mode, to find a nice piece of concreet.
> > After those 10 minutes it's gonna be a membership of the Martin Baker
> > Fanclub.
> Love the reference to Baker!!!

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CONTACTS:
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Mr. Eric Thomas
Product Support & Security Controller
Tel: +44 (0) 1895 836535


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Joint Managing Director


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

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seats.

Subsequent to her ejection she qualified as a pilot but was posted to a
transport squadron where she serves today as a Flight Lieutenant.

[Benjamin Gawert]

Eunometic schrieb:

> These EPS (Emergency Power System) Batteries are usually known as
> "Thermal Batteries". They have an eutectic electrolyte of salts that
> are melted by a pyrotechnical charge. Because the electrolyte is inert
> and sold untill melted shelf lives of 20+ years are possible. Because
> of the high opperating temperature very high power densities are
> possible.

The original PA200 EPS battery used liquid acid which when activated
flowed in precharged battery chambers. Due to several hazards that these
batteries incorporate they have been replaced by thermal batteries.

> 20 years would not be full life for an airliner and a ram air turbine I
> suggest would require less maintenance. (ie it doesn't ever need
> replacement)

Nope. A RAM air turbine _does_ indeed need maintenance, not only because
of aging seals and other items that have to be replaced from time to
time but also because it's a quite complicated mechanical part that has
to be checked in certain intervals to make sure it is in working condition.

RAM air turbines are certainly not a put-it-in-and-forget-it thing...

> The Panavia Tornado also has Nickel Cadmium Secondary rechargeable
> batteries (perhaps upgraded to NiMH now?) for APU starting and other
> power. I suspect that these could keep the system up for a few minutes
> on their own if in good condition.

Nope, the master battery (which is indeed NiMH now) only feeds certain
busbars that are required for start and is not suitable for emergency
operation...

>>I a lot of airplanes the APUs (resp. their intakes and exhausts) are
>>mounted in a way that they can't be used inflight.
>
>
> This would hardly apply to the Tornado.

It does apply for the PA200 Tornado. The APU is not operable in-flight,
if you loose both engines and the one-shot battery is down you have to
get out of that thing...

> Tornado however uses its
> entire slab sided botton fueselage for weapons: there is little room
> for ram air turbine.

Nope. It would be possible to integrate a RAM air turbine into the PA200
Tornado by relocating and re-arranging equipment in the lower
electronics bays. However, the efforts and also the cost are not
justifyable because a RAM air turbine would bring no real safety
imrpovement on the Tornado which already has a really very good safety
record, not to forget that it's old now and most airforces are planning
and/or already working on replacing it.

Benjamin

[Ian]

"Benjamin Gawert" > wrote in message
...
> Eunometic schrieb:
>
> > These EPS (Emergency Power System) Batteries are usually known as
> > "Thermal Batteries". They have an eutectic electrolyte of salts that
> > are melted by a pyrotechnical charge. Because the electrolyte is inert
> > and sold untill melted shelf lives of 20+ years are possible. Because
> > of the high opperating temperature very high power densities are
> > possible.
>
> The original PA200 EPS battery used liquid acid which when activated
> flowed in precharged battery chambers. Due to several hazards that these
> batteries incorporate they have been replaced by thermal batteries.
>
> > 20 years would not be full life for an airliner and a ram air turbine I
> > suggest would require less maintenance. (ie it doesn't ever need
> > replacement)
>
> Nope. A RAM air turbine _does_ indeed need maintenance, not only because
> of aging seals and other items that have to be replaced from time to
> time but also because it's a quite complicated mechanical part that has
> to be checked in certain intervals to make sure it is in working
condition.
>
> RAM air turbines are certainly not a put-it-in-and-forget-it thing...
>
> > The Panavia Tornado also has Nickel Cadmium Secondary rechargeable
> > batteries (perhaps upgraded to NiMH now?) for APU starting and other
> > power. I suspect that these could keep the system up for a few minutes
> > on their own if in good condition.
>
> Nope, the master battery (which is indeed NiMH now) only feeds certain
> busbars that are required for start and is not suitable for emergency
> operation...
>
> >>I a lot of airplanes the APUs (resp. their intakes and exhausts) are
> >>mounted in a way that they can't be used inflight.
> >
> >
> > This would hardly apply to the Tornado.
>
> It does apply for the PA200 Tornado. The APU is not operable in-flight,
> if you loose both engines and the one-shot battery is down you have to
> get out of that thing...
>
> > Tornado however uses its
> > entire slab sided botton fueselage for weapons: there is little room
> > for ram air turbine.
>
> Nope. It would be possible to integrate a RAM air turbine into the PA200
> Tornado by relocating and re-arranging equipment in the lower
> electronics bays. However, the efforts and also the cost are not
> justifyable because a RAM air turbine would bring no real safety
> imrpovement on the Tornado which already has a really very good safety
> record, not to forget that it's old now and most airforces are planning
> and/or already working on replacing it.
>
The F3 (ADV) has a RAT

[Big John]

Mu

Don't you mean the Caterpillar Club? I'm a member and people are
always asking me what the Pin is.

Big John
`````````````````````````````````````````````````` ```````````

On Thu, 15 Dec 2005 14:00:30 GMT,
(Mu) wrote:

>On 14 Dec 2005 22:43:21 -0800, "Charles Talleyrand"
> wrote:
>
>>Suppose a smaller airplane with it's fly-by-wire controls goes runs out
>>of fuel. All the engines quit. On a larger jet a ram air turbine
>>would drop into the airstream and power the controls. How does it work
>>on smaller planes like the Dassault Falcon or the F-16?
>>
>
>F16's have a EPU, and according to this link
>http://www.f-16.net/f-16_forum_viewtopic-t-1056.html you've got
>around 10 minutes in Hydrazine mode, to find a nice piece of concreet.
>After those 10 minutes it's gonna be a membership of the Martin Baker
>Fanclub.
>
>greetz Mu
>
>

[Benjamin Gawert]

Ian schrieb:

> The F3 (ADV) has a RAT

Really? Well, I only have experience with the GR versions which have a
one shot battery...

Benjamin

[Charles Talleyrand]

>> Alternatively, I've always wondered if one could not keep a special
>> reserve tank for the APU. When the engines quit, the APU
>> automatically starts to power the controls. Would such a system be
>> safe and would it be certifiable? Would it weigh less than the
>> existing system?

>In a lot of airplanes the APUs (resp. their intakes and exhausts) are
>mounted in a way that they can't be used inflight. Besides that, if
>there still is fuel in the tanks it's better served for keeping the
>engine alive than just the APU...

I know that most Boeing and Airbus planes can run the APU in the air.

I'm just asking if 30 minutes of fuel for the APU might not weigh less
than
the ram air turbine. The APU would clearly produce more power than the
ram air turbine.

If the choice was between flight controls powered for 30 minutes or the
main
engines powered for another one minite, I would take the former.

I must assume that there are some very smart aircraft designers who
have already
considered and rejected my idea. But WHY was this? Is it a
fundementally
bad idea, is it a good idea that's against the rules of certification,
or what?

-Charles Talleyrand

[Charles Talleyrand]

>Most pointedly they lost spoilers and flaps; they really only had a few
>instruments, ailerons, tail surfaces and the undercarriage. As a
>result of being without flaps the landing speed was very high and
>becuase there were no spoilers they couldn't loose speed or altitude
>and actually had to circle and zig zag to loose both speed an altitude.

What powered these controls?

I assume the insturments were powered by the ram air turbine, but
ailerons are BIG. What powered those?

-Thanks

[Ian]

"Benjamin Gawert" > wrote in message
...
> Ian schrieb:
>
> > The F3 (ADV) has a RAT
>
> Really? Well, I only have experience with the GR versions which have a
> one shot battery...
>
> Benjamin
Can't find a pic of where it is, but here's a pic of one of the external
gauges checked during pre-flight
http://www.tornado-data.com/History/airframe/ADV/pressures.htm

[Eunometic]

Benjamin Gawert wrote:
> Eunometic schrieb:
> It does apply for the PA200 Tornado. The APU is not operable in-flight,
> if you loose both engines and the one-shot battery is down you have to
> get out of that thing...

I didn't think Tornado was fully FBW?

[Benjamin Gawert]

Ian schrieb:

>>>The F3 (ADV) has a RAT
>>
>>Really? Well, I only have experience with the GR versions which have a
>>one shot battery...
>>
>>Benjamin
>
> Can't find a pic of where it is, but here's a pic of one of the external
> gauges checked during pre-flight
> http://www.tornado-data.com/History/airframe/ADV/pressures.htm

Thanks for the picture. It's really interesting, I never had to do with
the F series Tornados...

Benjamin

[Benjamin Gawert]

Eunometic schrieb:

>>Eunometic schrieb:
>>It does apply for the PA200 Tornado. The APU is not operable in-flight,
>>if you loose both engines and the one-shot battery is down you have to
>>get out of that thing...
>
>
> I didn't think Tornado was fully FBW?

The PA200 Tornado is fully FBW with a mechanical linkage backup system...

Benjamin

[Eunometic]

Benjamin Gawert wrote:
> Eunometic schrieb:
>
> >>Eunometic schrieb:
> >>It does apply for the PA200 Tornado. The APU is not operable in-flight,
> >>if you loose both engines and the one-shot battery is down you have to
> >>get out of that thing...
> >
> >
> > I didn't think Tornado was fully FBW?
>
> The PA200 Tornado is fully FBW with a mechanical linkage backup system...
>
> Benjamin

Then why does it need a thermal backup battery to remain airborn?

[Eunometic]

Benjamin Gawert wrote:
> Eunometic schrieb:
>
> >>Eunometic schrieb:
> >>It does apply for the PA200 Tornado. The APU is not operable in-flight,
> >>if you loose both engines and the one-shot battery is down you have to
> >>get out of that thing...
> >
> >
> > I didn't think Tornado was fully FBW?
>
> The PA200 Tornado is fully FBW with a mechanical linkage backup system...
>
> Benjamin

Then why does it need a thermal backup battery to remain airborn?

[Benjamin Gawert]

Eunometic schrieb:

>>The PA200 Tornado is fully FBW with a mechanical linkage backup system...
>>
>>Benjamin
>
>
> Then why does it need a thermal backup battery to remain airborn?

Because besides power for certain important instruments and the radio
the EPS battery also powers an electric motor that powers a hydraulic pump.

"Mechanical linkage" does not mean that the stick is connected to
pushrods and levers that move the control surfaces (which would be silly
on a fighter/bomber aircraft with up to ~55000 pounds weight). When in
so-called "mech mode" the stick is connected to several hydraulic valves
that control the hydraulic actuators. So you need hydraulics pressure,
and in cases of double engine out this hydraulic pressure comes from an
electric pump that powered by the EPS battery.

In normal operation the potentiometers connected to the stick submit
stick position data to the flight control system (CSAS and SPILS) which
calculate the necessary control surface deflection and control the
corresponding actuators. The mechanical linkage is inactive (in
emergencies the stick gets linked to the mechanical controls through a
honeycomb block which gets squeezed by the stick movement applied by the
panicing pilot ;-)

This applies to the GR versions (bomber), I don't know if the F versions
are somewhat different.

Benjamin

[Dan, U.S. Air Force, retired]

Charles Talleyrand wrote:
>>>Alternatively, I've always wondered if one could not keep a special
>>>reserve tank for the APU. When the engines quit, the APU
>>>automatically starts to power the controls. Would such a system be
>>>safe and would it be certifiable? Would it weigh less than the
>>>existing system?
>
>
>>In a lot of airplanes the APUs (resp. their intakes and exhausts) are
>>mounted in a way that they can't be used inflight. Besides that, if
>>there still is fuel in the tanks it's better served for keeping the
>>engine alive than just the APU...
>
>
> I know that most Boeing and Airbus planes can run the APU in the air.
>
> I'm just asking if 30 minutes of fuel for the APU might not weigh less
> than
> the ram air turbine. The APU would clearly produce more power than the
> ram air turbine.
>
> If the choice was between flight controls powered for 30 minutes or the
> main
> engines powered for another one minite, I would take the former.
>
> I must assume that there are some very smart aircraft designers who
> have already
> considered and rejected my idea. But WHY was this? Is it a
> fundementally
> bad idea, is it a good idea that's against the rules of certification,
> or what?
>
> -Charles Talleyrand
>

For one thing you'd be hard pressed to get 30 minutes of glide time
from any airliner.

Dan, U.S. Air Force, retired

[Keith W]

"Dan, U.S. Air Force, retired" > wrote in message
news:yDepf.66209$sg5.26836@dukeread12...
> Charles Talleyrand wrote:

>>
>
> For one thing you'd be hard pressed to get 30 minutes of glide time from
> any airliner.
>
> Dan, U.S. Air Force, retired

The Air Transat Airbus that ran out of fuel glided for 20 minutes
to get to the Azores

Keith

[Steve]

On Fri, 16 Dec 2005 22:57:37 +0100, Benjamin Gawert > wrote:

>Ian schrieb:
>
>> The F3 (ADV) has a RAT
>
>Really? Well, I only have experience with the GR versions which have a
>one shot battery...

Its located just behind the left main wheel but stalls when the gear is
lowered, so its a wheels up landing if you've got the balls. :)


--
Steve.

[Casey Wilson]

"Keith W" > wrote in message
...
>
> "Dan, U.S. Air Force, retired" > wrote in message
> news:yDepf.66209$sg5.26836@dukeread12...
>> Charles Talleyrand wrote:
>
>>>
>>
>> For one thing you'd be hard pressed to get 30 minutes of glide time
>> from any airliner.
>>
>> Dan, U.S. Air Force, retired
>
> The Air Transat Airbus that ran out of fuel glided for 20 minutes
> to get to the Azores
>
> Keith


And there is the 1983 (?86) story of the "Gimli Glider." An Air Canada
B-767 that ran out of fuel and landed on an X-ed out runway in Canada that
was, at the time, in use by sports car racers. See:

http://www.silhouet.com/motorsport/tracks/gimli.html

for a great photo. They talk about the RATS but I couldn't find any remarks
about elapsed glide time in this story.

For giggles, read the post script story about the mechanics who went to
rescue the airplane.

[Skywise]

"Casey Wilson" <N2310D @ gmail.com> wrote in
news:qokpf.21228$eI5.17594@trnddc05:

>
> "Keith W" > wrote in message
> ...
>>
>> "Dan, U.S. Air Force, retired" > wrote in message
>> news:yDepf.66209$sg5.26836@dukeread12...
>>> Charles Talleyrand wrote:
>>
>>>>
>>>
>>> For one thing you'd be hard pressed to get 30 minutes of glide time
>>> from any airliner.
>>>
>>> Dan, U.S. Air Force, retired
>>
>> The Air Transat Airbus that ran out of fuel glided for 20 minutes
>> to get to the Azores
>>
>> Keith
>
>
> And there is the 1983 (?86) story of the "Gimli Glider." An Air
> Canada
> B-767 that ran out of fuel and landed on an X-ed out runway in Canada
> that was, at the time, in use by sports car racers. See:
>
> http://www.silhouet.com/motorsport/tracks/gimli.html
>
> for a great photo. They talk about the RATS but I couldn't find any
> remarks about elapsed glide time in this story.
>
> For giggles, read the post script story about the mechanics who went to
> rescue the airplane.

HAHAHAHAA...too funny....I'd quote it but don't want to be
a spoiler.

I also liked the part about what was heard on the voice recorder
after the EICAS went "bong"..."Oh F___".

Damned good flying.

I would have officially christend that plane the "Gimli Glider"
and painted it's nose with it. I wonder if it's still in service
today. That plane's got good karma.

Brian
--
http://www.skywise711.com - Lasers, Seismology, Astronomy, Skepticism
Seismic FAQ: http://www.skywise711.com/SeismicFAQ/SeismicFAQ.html
Quake "predictions": http://www.skywise711.com/quakes/EQDB/index.html
Sed quis custodiet ipsos Custodes?
Like censorship and not getting support help? Switch to Supernews!
They won't even answer questions through your ISP!

[.Blueskies.]

"Casey Wilson" <N2310D @ gmail.com> wrote in message news:qokpf.21228$eI5.17594@trnddc05...
>
> "Keith W" > wrote in message ...
>>
>> "Dan, U.S. Air Force, retired" > wrote in message news:yDepf.66209$sg5.26836@dukeread12...
>>> Charles Talleyrand wrote:
>>
>>>>
>>>
>>> For one thing you'd be hard pressed to get 30 minutes of glide time from any airliner.
>>>
>>> Dan, U.S. Air Force, retired
>>
>> The Air Transat Airbus that ran out of fuel glided for 20 minutes
>> to get to the Azores
>>
>> Keith
>
>
> And there is the 1983 (?86) story of the "Gimli Glider." An Air Canada B-767 that ran out of fuel and landed on an
> X-ed out runway in Canada that was, at the time, in use by sports car racers. See:
>
> http://www.silhouet.com/motorsport/tracks/gimli.html
>
> for a great photo. They talk about the RATS but I couldn't find any remarks about elapsed glide time in this story.
>
> For giggles, read the post script story about the mechanics who went to rescue the airplane.
>

Here is a link to the RAT:
http://www.hamiltonsundstrandcorp.com/hsc/proddesc_display/0,4494,CLI1_DIV22_ETI2937_PRD38,00.html

We make the hydraulic pump portion:
http://www.parker.com//ead/cm2.asp?cmid=2841

[James Hart]

Skywise wrote:
> Damned good flying.
>
> I would have officially christend that plane the "Gimli Glider"
> and painted it's nose with it. I wonder if it's still in service
> today. That plane's got good karma.

http://www.airliners.net/search/photo.search?front=yes&maxres=500&keywords=C-GAUN

Still in service

[Benjamin Gawert]

Steve schrieb:

> Its located just behind the left main wheel but stalls when the gear is
> lowered, so its a wheels up landing if you've got the balls. :)

Well done ;-)

Benjamin

[Skywise]

"James Hart" > wrote in
:

> Skywise wrote:
>> Damned good flying.
>>
>> I would have officially christend that plane the "Gimli Glider"
>> and painted it's nose with it. I wonder if it's still in service
>> today. That plane's got good karma.
>
> http://www.airliners.net/search/photo.search?front=yes&maxres=500&keyword
> s=C-GAUN
>
> Still in service

Thank you!

Brian
--
http://www.skywise711.com - Lasers, Seismology, Astronomy, Skepticism
Seismic FAQ: http://www.skywise711.com/SeismicFAQ/SeismicFAQ.html
Quake "predictions": http://www.skywise711.com/quakes/EQDB/index.html
Sed quis custodiet ipsos Custodes?
Like censorship and not getting support help? Switch to Supernews!
They won't even answer questions through your ISP!

[Eunometic]

Benjamin Gawert wrote:
> Eunometic schrieb:
>
> >>The PA200 Tornado is fully FBW with a mechanical linkage backup system...
> >>
> >>Benjamin
> >
> >
> > Then why does it need a thermal backup battery to remain airborn?
>
> Because besides power for certain important instruments and the radio
> the EPS battery also powers an electric motor that powers a hydraulic pump.
>
> "Mechanical linkage" does not mean that the stick is connected to
> pushrods and levers that move the control surfaces (which would be silly
> on a fighter/bomber aircraft with up to ~55000 pounds weight).

Which means that PA200 Tornado when using 'mechanical' backup is
actually fully power opperated as opposed to power assisted (power
assisted can be designed to connect into a fully manual system with
limited movement). Given the need for power it doesn't seem to make
much sense to bother to use a mechanical system at all. An additional
layer of redundancy and an 'analog' backup would be better use of the
weight. Perhaps Panavia was worried about Electromagnetic Pulse or
Weapons. I believe F-16 uses fiber optics.

> When in
> so-called "mech mode" the stick is connected to several hydraulic valves
> that control the hydraulic actuators. So you need hydraulics pressure,
> and in cases of double engine out this hydraulic pressure comes from an
> electric pump that powered by the EPS battery.
>
> In normal operation the potentiometers connected to the stick submit
> stick position data to the flight control system (CSAS and SPILS) which
> calculate the necessary control surface deflection and control the
> corresponding actuators.

They use potentiometers? I though LVDT were normally used.

> The mechanical linkage is inactive (in
> emergencies the stick gets linked to the mechanical controls through a
> honeycomb block which gets squeezed by the stick movement applied by the
> panicing pilot ;-)
>
> This applies to the GR versions (bomber), I don't know if the F versions
> are somewhat different.
>
> Benjamin

[Eunometic]

A higher flying Airbus or B747-400 at 44,000ft might have glided nearly
30 minutes. This suggests that a fighter plane with its lower glide
ratio probably only needs half the amount of time (10 minutes) which
suggests that a thermal battery is possibly more efficient or at least
adaquet whereas an airliner may need twice as much.

What seems extraordinary is that both airbus and boeing designers have
provided insufficient RAT power to opperate all systems: spoilers,
flaps, undercarriage seem to be neglected. This makes an emegency
landing much harder. In both the airbus A330-200 azores and boeing 767
gimli fuel out landing case the lack of spoilers added a great deal of
risk as pilots manouvered agressively to loose altitude and speed for
runway lineup.

[Keith Willshaw]

"Eunometic" > wrote in message
ups.com...
>A higher flying Airbus or B747-400 at 44,000ft might have glided nearly
> 30 minutes. This suggests that a fighter plane with its lower glide
> ratio probably only needs half the amount of time (10 minutes) which
> suggests that a thermal battery is possibly more efficient or at least
> adaquet whereas an airliner may need twice as much.
>
> What seems extraordinary is that both airbus and boeing designers have
> provided insufficient RAT power to opperate all systems: spoilers,
> flaps, undercarriage seem to be neglected. This makes an emegency
> landing much harder. In both the airbus A330-200 azores and boeing 767
> gimli fuel out landing case the lack of spoilers added a great deal of
> risk as pilots manouvered agressively to loose altitude and speed for
> runway lineup.
>

If you add more power to the RAT you increase drag and reduce the
glide distance, the record suggests they made the right trade offs.

Keith

[Ian]

"Eunometic" > wrote in message
oups.com...
>
> Benjamin Gawert wrote:
> > Eunometic schrieb:
> >
> > >>Eunometic schrieb:
> > >>It does apply for the PA200 Tornado. The APU is not operable
in-flight,
> > >>if you loose both engines and the one-shot battery is down you have to
> > >>get out of that thing...
> > >
> > >
> > > I didn't think Tornado was fully FBW?
> >
> > The PA200 Tornado is fully FBW with a mechanical linkage backup
system...
> >
> > Benjamin
>
> Then why does it need a thermal backup battery to remain airborn?
>
The One Shot Battery is there to provide electrical power to a Fuel pump (or
in combination with a Hyd pump). The engines also need electrical power to
keep their systems running - without electrics, the engines will "run
away" - Very bad thing if you're not near a nice big bit of tarmac......

[Benjamin Gawert]

Eunometic schrieb:

>>"Mechanical linkage" does not mean that the stick is connected to
>>pushrods and levers that move the control surfaces (which would be silly
>> on a fighter/bomber aircraft with up to ~55000 pounds weight).
>
>
> Which means that PA200 Tornado when using 'mechanical' backup is
> actually fully power opperated as opposed to power assisted (power
> assisted can be designed to connect into a fully manual system with
> limited movement).

correct.

> Given the need for power it doesn't seem to make
> much sense to bother to use a mechanical system at all.

The mechanical linkage backup is there if the 2x redundant fly-by-wire
system fails or gets damaged. When in "mech mode" (FBW dead but engines
are running) the aircraft is fully controllable (but of course reacts
more sensible due to the lack of CSAS and also lacks things like spin
prevention and AOA limiter etc). Loosing the FBW does not mean the
aircraft can't return safely...

> An additional
> layer of redundancy and an 'analog' backup would be better use of the
> weight. Perhaps Panavia was worried about Electromagnetic Pulse or
> Weapons.

Correct. Thanks to the mechanical linkage the aircraft is still operable
even when suffering from an EMP or with a damaged electronics system.
Even 4x redundant FBW wouldn't provide this safety, and the weight
penalty isn't really big.

> I believe F-16 uses fiber optics.

The Eurofighter Typhoon uses fiber optics. The F-16 used a wire harness
(don't know if that has been changed in a later block but I doubt that).

>>In normal operation the potentiometers connected to the stick submit
>>stick position data to the flight control system (CSAS and SPILS) which
>>calculate the necessary control surface deflection and control the
>>corresponding actuators.
>
>
> They use potentiometers? I though LVDT were normally used.

No, it's some sort of potentiometer, but of course a bit more
sophisticated than what you can find in consumer electronics ;-)

Benjamin

[Mu]

On Mon, 19 Dec 2005 19:59:21 +0100, Benjamin Gawert >
wrote:

>Eunometic schrieb:
>
>>>"Mechanical linkage" does not mean that the stick is connected to
>>>pushrods and levers that move the control surfaces (which would be silly
>>> on a fighter/bomber aircraft with up to ~55000 pounds weight).
>>
>>
>> Which means that PA200 Tornado when using 'mechanical' backup is
>> actually fully power opperated as opposed to power assisted (power
>> assisted can be designed to connect into a fully manual system with
>> limited movement).
>
>correct.
>
>> Given the need for power it doesn't seem to make
>> much sense to bother to use a mechanical system at all.
>
>The mechanical linkage backup is there if the 2x redundant fly-by-wire
>system fails or gets damaged. When in "mech mode" (FBW dead but engines
>are running) the aircraft is fully controllable (but of course reacts
>more sensible due to the lack of CSAS and also lacks things like spin
>prevention and AOA limiter etc). Loosing the FBW does not mean the
>aircraft can't return safely...
>

Hmm sounds sensible in a Cold War environment with buckets of canned
sunshine being thrown around.

But now a question to pilots or folks in the know:
Do they train flying "mech mode" and if so how?
Just in the sims or sometimes for real as in.
"IP to student: I flipped the switch to mech mode. Show me how you
smooth you can land this baby"?

And if a pilot can apparently fly safe in "mech mode" does that mean
that the Tornado is not inherent unstable like the F16? Or at least
not very inherent unstable?

Because flying a F16 in "mech mode" (if that beast would exist) THAT
would be a real challange.

Greetz Mu




Greetz Mu

[Dan, U.S. Air Force, retired]

Ian wrote:
> "Eunometic" > wrote in message
> oups.com...
>
>>Benjamin Gawert wrote:
>>
>>>Eunometic schrieb:
>>>
>>>
>>>>>Eunometic schrieb:
>>>>>It does apply for the PA200 Tornado. The APU is not operable
>
> in-flight,
>
>>>>>if you loose both engines and the one-shot battery is down you have to
>>>>>get out of that thing...
>>>>
>>>>
>>>>I didn't think Tornado was fully FBW?
>>>
>>>The PA200 Tornado is fully FBW with a mechanical linkage backup
>
> system...
>
>>>Benjamin
>>
>>Then why does it need a thermal backup battery to remain airborn?
>>
>
> The One Shot Battery is there to provide electrical power to a Fuel pump (or
> in combination with a Hyd pump). The engines also need electrical power to
> keep their systems running - without electrics, the engines will "run
> away" - Very bad thing if you're not near a nice big bit of tarmac......
>
>
Or, more importantly, a runway. They tend to be made of concrete not
asphalt.

Dan, U.S. Air Force, retired

[Eunometic]

Keith Willshaw wrote:
> "Eunometic" > wrote in message
> ups.com...
> >A higher flying Airbus or B747-400 at 44,000ft might have glided nearly
> > 30 minutes. This suggests that a fighter plane with its lower glide
> > ratio probably only needs half the amount of time (10 minutes) which
> > suggests that a thermal battery is possibly more efficient or at least
> > adaquet whereas an airliner may need twice as much.
> >
> > What seems extraordinary is that both airbus and boeing designers have
> > provided insufficient RAT power to opperate all systems: spoilers,
> > flaps, undercarriage seem to be neglected. This makes an emegency
> > landing much harder. In both the airbus A330-200 azores and boeing 767
> > gimli fuel out landing case the lack of spoilers added a great deal of
> > risk as pilots manouvered agressively to loose altitude and speed for
> > runway lineup.
> >
>
> If you add more power to the RAT you increase drag and reduce the
> glide distance, the record suggests they made the right trade offs.

Apparently in the the lockheed L.1011 Tristar The RAT pressurises a
hydraulic system that can be connected through to the undercarriage,
flaps, spoilers although the system becomes quite sluggish in this mode
and one would expect the pilots to time this opperation carefully.

I would like to see some sort of one shot Emergency Power System EPS
such as a thermal battery to provide supplementary power to allow full
flight control opperation for final 5-7 minutes of flight. There may
be safety issues related to chemical power sources (eg hot thermal
batteries with very high current output or hydrazine gas generators in
a crash) Clearly in fighter aircraft the intention is to allow the
aircraft to get into an ejection zone.

Poor L.1011: a fine piece of advanced engineering that was a commercial
failure (due to delays on the RB.211 engine I think)






(an excellent aircraft in engineering terms that was a commercial
failure)


>
> Keith

[Eunometic]

John Carrier wrote:
> Glide speed generally provides sufficient windmill RPM on the engine(s) to
> provide sufficient hydraulic power so that the controls (they don't have to
> be fly-by-wire, any irreversible hyd flight control system is effected) have
> sufficient pressure and volume to operate normally with moderate control
> inputs.
>
> R / John
>

The B747 and B737 (not sure about the B737 NG aircraft) uses
windmilling of main engines for providing hydralic power but also has
substantial battery backup to provide electrical power. FBW aircraft
are more dependent on electrical power so tend to use RATS but
B747/B737 have power or power assisted controls but not FBW.

The RAT generates hydraulic pressure for the flight controls and then
derive electrical power from a hydraulic motor driven generator.

I believe the DC10/MD11 used ATG (Air Turbine Generator) and thus
reversed the setup with the turbine driving a generator to power a
electrical bus and then deriving hydraulic power from this.

VC10 had both a RAT for Hydraulic power and ATG for electrical.

APU's generally can't be started reliably in flight but 3+ hour ETOPS
certified aircraft like the B777 have special APU that are certified to
start after a cold soak.

[Benjamin Gawert]

Mu schrieb:

> Hmm sounds sensible in a Cold War environment with buckets of canned
> sunshine being thrown around.

Well, the PA200 is a aircraft from the cold war aera...

> But now a question to pilots or folks in the know:
> Do they train flying "mech mode" and if so how?
> Just in the sims or sometimes for real as in.
> "IP to student: I flipped the switch to mech mode. Show me how you
> smooth you can land this baby"?

No real training in mech mode (mech mode is an emergency system and not
selectable by a switch, and having it activated once means that after
the aircraft is back on the ground it has to go to service for having
the honeycomb package replaced). You can train that in the simulator,
but usually there is no special training for flying in mech mode...

> And if a pilot can apparently fly safe in "mech mode" does that mean
> that the Tornado is not inherent unstable like the F16? Or at least
> not very inherent unstable?

No, it's not. The PA200 is a very stable aircraft, there are no real
surprises for the pilot when in mech mode. There is a little yaw
tendency that gets suppressed by the yaw damper in CSAS and that shows
up in mech mode, and you loose functions like auto rudder or SPILS (spin
preventer/AOA limiter), stick feel simulation and such. Nothing which is
really a problem for emergency operation...

Benjamin

[Morgans]

"Eunometic" > wrote

ETOPS ???
--
Jim in NC

[Jose]

> ETOPS ???

"Engine turns or people swim". It has an official name too, it is part
of special certification of twins for long range overwater operations
(otherwise you need more engines)

Jose
--
You can choose whom to befriend, but you cannot choose whom to love.
for Email, make the obvious change in the address.

[Thomas Schoene]

Morgans wrote:
> "Eunometic" > wrote
>
> ETOPS ???

Extended-range Twin-engine Operation Performance Standards.

Basically, it means the aircraft can operate overwater* as long as it is
within X minutes from a divert airfield (where X is anywhere from 75
minutes to 180 minutes). The idea is that an ETOPS-rated twin-engine
aircraft is reliable enough that even if one engine fails the other will
keep running and keep the plane flying at least the rated time, so that
a safe landing is possible.



*Technically, anywhere more than 1 hour from a divert field, so ETOPS
applies to long-range overland routes too, but the oceanic routes were
the main drivers.

--
Tom Schoene
To email me, replace "invalid" with "net"

[Steve]

On Mon, 19 Dec 2005 00:47:23 +0100, Benjamin Gawert > wrote:

>Steve schrieb:
>
>> Its located just behind the left main wheel but stalls when the gear is
>> lowered, so its a wheels up landing if you've got the balls. :)
>
>Well done ;-)

Thankyou :-)

And for a bonus point, its not much use below 200Kts anyway.


--
Steve.

[Steve]

On Tue, 20 Dec 2005 13:52:11 +0100, Benjamin Gawert > wrote:

>> And if a pilot can apparently fly safe in "mech mode" does that mean
>> that the Tornado is not inherent unstable like the F16? Or at least
>> not very inherent unstable?
>
>No, it's not. The PA200 is a very stable aircraft, there are no real
>surprises for the pilot when in mech mode.

A bit sensitive in pitch maybe? :-)

Theres a video at the link below of a GR1 doing a mech-mode approach,
although thats not what the vid is about, hehe. Scroll down to 'Bonus' and
its the 'Near miss' video. A hairy situation.

http://www.fromtheflightdeck.com/videos/index.htm


--
Steve.

[Jack]

Steve wrote:

> Theres a video at the link below of a GR1 doing a mech-mode approach,
> although thats not what the vid is about, hehe. Scroll down to 'Bonus' and
> its the 'Near miss' video. A hairy situation.
>
> http://www.fromtheflightdeck.com/videos/index.htm

Don't you just hate people who don't have their checklists completed
when the take the active? ;>


Jack

[Benjamin Gawert]

Steve schrieb:

>>No, it's not. The PA200 is a very stable aircraft, there are no real
>>surprises for the pilot when in mech mode.
>
>
> A bit sensitive in pitch maybe? :-)

With wings at 25 degrees the Tornado is quite sensitive in pitch, even
with FBW. Especially since approaches and take offs are done with
deactivated SPILS...

> Theres a video at the link below of a GR1 doing a mech-mode approach,
> although thats not what the vid is about, hehe. Scroll down to 'Bonus' and
> its the 'Near miss' video. A hairy situation.
>
> http://www.fromtheflightdeck.com/videos/index.htm

Nice video. This btw happened in Decimomannu/Italy when the tower
"forgot" about a italian Tornado waiting for T/O clearance and allowed a
German Tornado to land...

Benjamin

[Steve]

On Sat, 24 Dec 2005 21:21:50 +0100, Benjamin Gawert > wrote:

>> http://www.fromtheflightdeck.com/videos/index.htm
>
>Nice video. This btw happened in Decimomannu/Italy when the tower
>"forgot" about a italian Tornado waiting for T/O clearance and allowed a
>German Tornado to land...

Ah, didn't know it was at Deci. Thought it happened in UK but with an
Italian exchange student in the front and moaning mini in the back. :-) Did
the GR see the F2 in time or was it a red flare job? Heard the F2 crew had
to scrub due to shock.


--
Steve.

[Benjamin Gawert]

Steve schrieb:

> Ah, didn't know it was at Deci. Thought it happened in UK but with an
> Italian exchange student in the front and moaning mini in the back. :-) Did
> the GR see the F2 in time or was it a red flare job? Heard the F2 crew had
> to scrub due to shock.

IIRC the GR recognized in the last moment that the space on the runway
was already occupied ;-)

It looks ridiculous but sadly things like that happen. Aircrafts in
bright grey like the italian Tornado are very hard to see from above,
and if the tower personel is having a nap then **** like this happens.
If the pilot hadn't seen the F.3 in time then this probably would have
resulted in a crash...

Benjamin