skyhigh777
Topic Author
Posts: 335
Joined: Sun Aug 14, 2005 7:07 am

Reverse Thrust Deployed Before Landing

Sat Nov 26, 2005 4:35 pm

Is it possible to have the reverse thrusters deployed before the aircraft has landed? I dont know if I am wrong, but I have never seen this happen before and always thought that the airplane won't let you deploy reverse thrusters unless the plane is on the ground. Is this common only to Russian-made aircrafts?


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Photo © José Geraldes



Thanks,
SkyHigh777

[Edited 2005-11-26 08:36:33]
 
je89_w
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RE: Reverse Thrust Deployed Before Landing

Sat Nov 26, 2005 4:44 pm

Yes, I believe this is only done by Russian aircraft.

I remember debates about this photo on the forums years ago:

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Photo © Michael F. McLaughlin


It turned out that it was paint on the engine, but it does look like it is half open.

Don't forget the Lauda B763 that crashed off BKK in 1991. It had its thrust reversers deployed after takeoff, causing the crew to lose control of the plane.

"According to the official accident report, as that airliner continued to climb some 45 minutes after take-off from Bangkok, the pilots noticed a warning light alerting them to a thrust reverser problem.

Minutes later, a hydraulic activator pin triggered the reverser to open, creating a catastrophic spin.

With the thrust from the two engines flowing in opposite directions, the pilots could not control the aircraft and it plunged to earth.

After months of investigation, the US Federal Aviation Administration ordered manufacturers to re-engineer thrust reversers on all US-registered Boeing 767s.
"

http://news.bbc.co.uk/1/hi/sci/tech/503780.stm

RIP.

[Edited 2005-11-26 08:54:01]
 
dogfighter2111
Posts: 1867
Joined: Tue Nov 09, 2004 3:02 am

RE: Reverse Thrust Deployed Before Landing

Sat Nov 26, 2005 4:52 pm

The Tridents were able to deploy speedbrakes whilst at cruisng altitude to sloe the descent.

Thanks
Mike
 
Glareskin
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RE: Reverse Thrust Deployed Before Landing

Sat Nov 26, 2005 4:56 pm

Quoting Je89_w (Reply 1):
Don't forget the Lauda B763.

Yes but this was obviously not supposed to happen.... There was a warning signal in the cockpit that something was wrong but it was ignored by the crew. Human error!
http://www.airdisaster.com/cgi-bin/v...05261991®=OE-LAV&airline=Lauda+Air
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skyhigh777
Topic Author
Posts: 335
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RE: Reverse Thrust Deployed Before Landing

Sat Nov 26, 2005 5:03 pm

Didn't it also happen on an Alaska Airlines flight that crashed off the coast of Southern CA?
 
dogfighter2111
Posts: 1867
Joined: Tue Nov 09, 2004 3:02 am

RE: Reverse Thrust Deployed Before Landing

Sat Nov 26, 2005 5:03 pm

Quoting Glareskin (Reply 3):
There was a warning signal in the cockpit that something was wrong but it was ignored by the crew. Human error!

That is true but if they had turned to go back to the airport then it could be 20mins until they were on approach and the Reverse Thrust may have been deployed then and it may have caused more deaths by people on the ground.

I do understand how it was human error though, there was no attempt made to return.

Thanks
Mike
 
dogfighter2111
Posts: 1867
Joined: Tue Nov 09, 2004 3:02 am

RE: Reverse Thrust Deployed Before Landing

Sat Nov 26, 2005 5:11 pm

Quoting SkyHigh777 (Reply 4):
Didn't it also happen on an Alaska Airlines flight that crashed off the coast of Southern CA?

Hey,

That was a failure with the "Jackscrew assembly acme nut thread", wow what a mouthful  Smile It had not been lubricated enough and jammed the stabalizer.

Thanks
Mike
 
speedbrds
Posts: 58
Joined: Sat Jun 18, 2005 1:32 pm

RE: Reverse Thrust Deployed Before Landing

Sat Nov 26, 2005 5:12 pm

The only aircraft that I know that can use revers thrust in-flight (airborne) was the Concorde. The use it to slow down and/or steep descents from high altitudes.
 
pilotpip
Posts: 2843
Joined: Fri Sep 19, 2003 3:26 pm

RE: Reverse Thrust Deployed Before Landing

Sat Nov 26, 2005 5:17 pm

DC-8s can also do this with the inboards because they have a clean wing (no speedbrakes or spoilers).
DMI
 
HS748
Posts: 621
Joined: Tue Oct 11, 2005 3:01 am

RE: Reverse Thrust Deployed Before Landing

Sat Nov 26, 2005 5:19 pm

Quoting Glareskin (Reply 3):
Yes but this was obviously not supposed to happen.... There was a warning signal in the cockpit that something was wrong but it was ignored by the crew. Human error!

It wasn't ignored by the crew. They assessed the situation and decided to continue. It may have been the wrong decision to make but they didn't ignore the warning.
 
skyhigh777
Topic Author
Posts: 335
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RE: Reverse Thrust Deployed Before Landing

Sat Nov 26, 2005 5:23 pm

Wouldn't the deployment of the reverse thrusters when the plane is about to land be dangerous and cause the airplane to drop suddenly and much harder during the landing?
 
dogfighter2111
Posts: 1867
Joined: Tue Nov 09, 2004 3:02 am

RE: Reverse Thrust Deployed Before Landing

Sat Nov 26, 2005 5:25 pm

Quoting SkyHigh777 (Reply 10):
Wouldn't the deployment of the reverse thrusters when the plane is about to land be dangerous and cause the airplane to drop suddenly and much harder during the landing?

Yes, but if the aircraft like Concorde, Trident and Russian Aircraft can handle reverse thrust whilst still in the air it should be fine.

If a B744 done it then youd have a rough landing.

Thanks
Mike
 
star_world
Posts: 943
Joined: Mon Jun 25, 2001 7:52 am

RE: Reverse Thrust Deployed Before Landing

Sat Nov 26, 2005 5:27 pm

Quoting Speedbrds (Reply 7):
The only aircraft that I know that can use revers thrust in-flight (airborne) was the Concorde. The use it to slow down and/or steep descents from high altitudes.

I don't believe this is (was!) the case - the following site has some very detailed information on the Concorde design, and doesn't mention this at all:

http://www.concordesst.com/powerplant.html
 
BCAL
Posts: 2925
Joined: Mon Jun 28, 2004 10:16 pm

RE: Reverse Thrust Deployed Before Landing

Sat Nov 26, 2005 9:18 pm

Quoting Dogfighter2111 (Reply 2):
The Tridents were able to deploy speedbrakes whilst at cruisng altitude to sloe the descent

With thanks to Stratocruiser, who I believe mentioned he had experienced it on a Trident flight, and Trident 3, I found the following quotes in the archives

Quote:
The Trident could actually use reverse thrust in normal flight, not just right before landing - it could be used if a rapid decent was required by ATC and indeed it could drop like a stone! The subject of the Trident being certified to use reverse thrust in flight, this was mentioned on a recent programme in the Discovery channel series Classic British Aircraft. An ex Trident captain mentioned that the plane could descend from 20,000 to ground in less than 2 mins. The trouble was this was faster than the presurisation system could cope with so the flight engineer had to start depresurising the cabin before the aircraft started to descend.
MOL on SRB's latest attack at BA: "It's like a little Chihuahua barking at a dying Labrador. Nobody cares."
 
viscount630
Posts: 171
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RE: Reverse Thrust Deployed Before Landing

Sat Nov 26, 2005 10:00 pm

Quoting Pilotpip (Reply 8):
DC-8s can also do this with the inboards because they have a clean wing (no speedbrakes or spoilers).

Indeed. I actually had experience of this on a UA DC-8-70 DEN-EWR flight. The Captain actually warned passengers he would be doing it (to aid manouverability during the approach in the busy NY area I think he said.....) It was quite a strange sensation during the decent - very different to ordinary speed-brakes and flaps being deployed.  spin 
RIP Dan-Air. Where the Secret was SERVICE.
 
md80fanatic
Posts: 2365
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RE: Reverse Thrust Deployed Before Landing

Sat Nov 26, 2005 10:21 pm

Quoting Viscount630 (Reply 14):
It was quite a strange sensation during the decent - very different to ordinary speed-brakes and flaps being deployed.

 Smile It's good to know that there are still people around that can distinguish one acceleration from another.  duck 
 
bennett123
Posts: 9221
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RE: Reverse Thrust Deployed Before Landing

Sat Nov 26, 2005 10:36 pm

http://aviation-safety.net/database/record.php?id=19700915-0

Clearly it was possible with the DC8, but not always advisable.
 
Devil505x
Posts: 220
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RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 1:07 am

I could be wrong but wasn't there a crash (DC-10?) where the pilots put the engines into reverse at cruise altitude to see what would happen. The result was the aircraft's destruction. If anyone could help please fill me in.
 
KLA
Posts: 1
Joined: Mon Oct 10, 2005 10:31 pm

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 1:08 am

It is possible to deploy the reverse on the MD80, however only if you are in idle thrust. Once you advance the thrust levers you can no longer lift the reverse levers.

I have even heard of some old pilots deploying the reverse just before landing as it aids the smoothness of the landing it self.

But none of the above is a used procedure on the MD80.
 
eaglekeeper101
Posts: 269
Joined: Fri Aug 05, 2005 8:14 am

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 1:17 am

Is it not true that on the IL-62, only the outboard engines have thrust reversers? If so, at least the inboards would be pointed in the right direction whilst the outboards were reversed, so to speak.
"The earth is but one country, and mankind its citizens." - Bahá'u'lláh
 
viscount630
Posts: 171
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RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 1:17 am

Quoting MD80fanatic (Reply 15):
It's good to know that there are still people around that can distinguish one acceleration from another.

What can I tell ya? It just felt very different - very different noises certainly and like going down a lift shaft instead of sliding down a hill......? Which is probably why the Captain felt fit to warn us before he launched us into it......  Cool
RIP Dan-Air. Where the Secret was SERVICE.
 
boeingpride800
Posts: 391
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RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 1:22 am

I was on a NW 757 coming into Detroit onetime, and the pilot deployed the speed breaks. It was probably 35 minutes before landing and he did it because of traffic congestion at the airport. It was quite interesting to see.
 
Accidentally
Posts: 613
Joined: Sun Dec 10, 2000 7:33 am

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 1:22 am

Quoting Star_world (Reply 12):
I don't believe this is (was!) the case - the following site has some very detailed information on the Concorde design, and doesn't mention this at all:

He is certainly correct. Concorde's inboard reversers could be used in-flight.
Indianapolis, IN
 
JBirdAV8r
Posts: 3460
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RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 1:27 am

Quoting Devil505x (Reply 17):
I could be wrong but wasn't there a crash (DC-10?) where the pilots put the engines into reverse at cruise altitude to see what would happen. The result was the aircraft's destruction. If anyone could help please fill me in.

I think you might be thinking of a National DC-10 where the crew was "experimenting" with the engine, oversped it, and it caused an uncontained engine failure where turbine blades pierced the cabin. EDIT: Turns out one passenger was sucked out a window that was blown out by flying debris. Ouch. I can't think of a worse way to go...

http://www.airdisaster.com/user-uploads/Na-1.JPG

[Edited 2005-11-26 17:28:27]

[Edited 2005-11-26 17:38:25]
I got my head checked--by a jumbo jet
 
AvFan4ever
Posts: 80
Joined: Sat Feb 05, 2005 7:07 pm

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 2:40 am

Quoting JBirdAV8r (Reply 23):
and it caused an uncontained engine failure where turbine blades pierced the cabin.

The engine in the photo looks like it suffered an uncontained failure of a fan blade or a ruptured fan disk, rather than a turbine failure.
 
scxmechanic
Posts: 479
Joined: Sat Dec 25, 1999 10:20 am

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 3:13 am

The DC-10 and the B737-3/4/500 and NG's can deploy the reverser's if the aircraft is below 10 Ft. radio altitude.

Not advisable but its able to do it. Only idle thrust can be obtained till the aircraft is on the ground.

I was on the jumpseat once in the DC-10 when the Capt accidentally deployed the T/R's within that 10 Ft. and we hit like a ton of bricks. Thank God it was only a ferry flight. Just the flight crew, some flight attendants and myself.

I spent many a mile riding airplanes around the world as a flight mechanic and never had a landing SO hard.
 
idlewild
Posts: 118
Joined: Fri Jun 10, 2005 8:16 am

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 3:21 am

I remember 20 + years ago when a JAL DC-8 smacked into a bay less than a mile from an airport in Japan because the captain decided to reverse. They attributed it to suicidal tendencies.
 
JBirdAV8r
Posts: 3460
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RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 3:28 am

Quoting AvFan4ever (Reply 24):
The engine in the photo looks like it suffered an uncontained failure of a fan blade or a ruptured fan disk, rather than a turbine failure.

A little "po-tay-to" "po-tah-to" misunderstanding. I said "turbine" when I meant "fan"...I was thinking about N1...my, aren't we picky  sarcastic 
I got my head checked--by a jumbo jet
 
Devil505x
Posts: 220
Joined: Sat Dec 20, 2003 3:55 am

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 3:32 am

Quoting JBirdAV8r (Reply 23):
I think you might be thinking of a National DC-10 where the crew was "experimenting"

I believe that was it. I wonder what happened to the pilots? Murder charges?
 
AngelAirways
Posts: 481
Joined: Wed Nov 10, 1999 3:55 am

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 4:28 am

Actually...

the IL-62 deploys thrust reversers just as it crosses the runway threshold (the point at which most other airliners pull the levers back to idle)


and the reason it needs to do that is because, due to its aerodynamic configuration and design, its landing speed is high and its low wing means it tends to float in ground effect just above the runway for quite a long distance before touching down. the inboard engines are idle while the outboard ones work in reverse.

as regards spoilers.. they can be deployed by most modern airliners in cruise for either

- turning (as an inboard aileron) or
- urgent deceleration/descent, especially in tight traffic patterns
 
sonic67
Posts: 287
Joined: Mon Jan 24, 2005 2:43 pm

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 4:43 am

Quoting AngelAirways (Reply 29):
the IL-62 deploys thrust reversers just as it crosses the runway threshold (the point at which most other airliners pull the levers back to idle)

YEAH what he said.

Also the IL-62 only has thrust reverse on the # 1 and 4 engines they still can use 2 and 3 engines if needed.
 
dtwclipper
Posts: 6668
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RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 4:45 am

Quoting Viscount630 (Reply 14):
Quoting Pilotpip (Reply 8):
DC-8s can also do this with the inboards because they have a clean wing (no speedbrakes or spoilers).

Indeed. I actually had experience of this on a UA DC-8-70 DEN-EWR flight. The Captain actually warned passengers he would be doing it (to aid manouverability during the approach in the busy NY area I think he said.....) It was quite a strange sensation during the decent - very different to ordinary speed-brakes and flaps being deployed.

I had the same thing happen on an Icelandic DC-8, west bound into JFK.

It was very odd, the entire cabin shook for a while.
Compare New York Air, the Airline that works for your Business
 
AR385
Posts: 6929
Joined: Fri Nov 07, 2003 8:25 am

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 4:49 am

Quoting AngelAirways (Reply 29):
Actually...

the IL-62 deploys thrust reversers just as it crosses the runway threshold (the point at which most other airliners pull the levers back to idle)

This is correct, but adding to that excellent explanation, Soviet aircraft did not have spoilers until the Tu-154 came around. So, they frequently busted speed limits in the West. Since the Soviets did not have the technology for designing spoilers, they equipped their aircraft with the ability to have their thrust reversers functional in flight. This "knowhow" was probably added to the IL-62 as an added feature.
 
alphaomega
Posts: 267
Joined: Fri Aug 26, 2005 1:26 pm

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 5:44 am

I'm not sure if all Gulfsteams are able to, but the shuttle training aircraft used by NASA climbs up to 35,000 and then deploys the thrust reversers to simulate a shuttle approach and landing.
 
Tristarsteve
Posts: 3643
Joined: Tue Nov 22, 2005 11:04 pm

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 5:48 am

The Trident 2E had such a good rate of descent with reversers deployed that it was not equipped with a passenger oxygen system. With a pressurisation failure at cruising altitude it could get down to 10000 in the two mins stipulated by BCARs.

By the way don't go looking for a Trident with thrust reverse deployed. It was all internal to the jet pipe and you couldn't tell if it was deployed or not by looking at it.
 
airfoilsguy
Posts: 3485
Joined: Sun Oct 09, 2005 7:28 am

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 6:02 am

Quoting Glareskin (Reply 3):
s but this was obviously not supposed to happen.... There was a warning signal in the cockpit that something was wrong but it was ignored by the crew. Human error!

Human error maybe, but not the humans flying the plane. This quoted from below source

http://aviation-safety.net/database/record.php?id=19910526-0

The crew didn't take immediate action, since the 767 Emergency/Malfunction Checklist said 'No action required'

[Edited 2005-11-26 22:18:33]
It's not a near miss it's a near hit!!
 
noelg
Posts: 2313
Joined: Fri Apr 26, 2002 11:39 pm

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 6:09 am

Gabon Express' Caravelles used to routinely deploy reversers before landing at certain airports in Africa.


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Photo © Jan Mogren



One beautiful aircraft!


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Photo © Jan Mogren

 
Devil505x
Posts: 220
Joined: Sat Dec 20, 2003 3:55 am

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 6:20 am

Quoting AR385 (Reply 32):
Since the Soviets did not have the technology for designing spoilers, they equipped their aircraft

I don't know but how hard can spoliers be to design?
 
Lairyliam
Posts: 70
Joined: Wed May 19, 2004 9:21 pm

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 6:42 am

Quoting Dogfighter2111 (Reply 6):
Hey,

That was a failure with the "Jackscrew assembly acme nut thread",

Respect for that mouthful!!!!  bigthumbsup 
12MILES NNE OF THE IOM VOR
 
DCrawley
Posts: 328
Joined: Mon Jun 06, 2005 3:18 am

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 7:28 am

Quoting Speedbrds (Reply 7):
The only aircraft that I know that can use revers thrust in-flight (airborne) was the Concorde. The use it to slow down and/or steep descents from high altitudes.

Don't forget the C-17 Globemaster III. The USAF uses it for combat descents (I think that's what they called it.. will have to call a buddy who flies 'em and double check tomorrow). 30 degrees nose down + full reverse thrust = hanging on by your harness! Here's a little bit I found on the reverse thrust system:

The C-17 measures approximately 174 feet long with a 170-foot wingspan. The aircraft is powered by four fully reversible Pratt & Whitney F117-PW-100 engines (the commercial PW2040 series version is currently used on the Boeing 757). Each engine produces 40,440 pounds of thrust, located on pylons ahead of and below the wing leading edge. The engines are equipped with directed-flow thrust reversers capable of deployment in flight. On the ground, a fully loaded aircraft, using engine reversers, can back up a two percent slope. The thrust reversers direct the flow of air upward and forward to avoid ingestion of dust and debris. Combined with propulsive lift, the advanced thrust reversers enables short landings. The thrust reversers are an integral part of the C-17 nacelle. When thrust reversal is initiated, both fan and core exhausts are redirected. Thrust is directed forward and upward through exposed louvers for maximum reverse thrust. During ground operations, the thrust reversers can be deployed with engines idling, directing engine blast away from personnel working cargo.

C-17 Globemaster III

Quoting MD80fanatic (Reply 15):
It's good to know that there are still people around that can distinguish one acceleration from another.

I don't know if acceleration is the correct word to use in this situation.. I think you're making a steeper descent and maintaining speed, but I'm not positive as I've never operated RT other than landing.

-d
"Weather at our destination is 50 degrees with some broken clouds, but they'll try to have them fixed before we arrive."
 
KC135R
Posts: 696
Joined: Sun May 01, 2005 6:38 am

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 9:25 am

Quoting DCrawley (Reply 39):
The USAF uses it for combat descents

The use of TR's in flight would be for an assault landing, that is the descent you are describing.

Quoting BoeingPride800 (Reply 21):
I was on a NW 757 coming into Detroit onetime, and the pilot deployed the speed breaks. It was probably 35 minutes before landing and he did it because of traffic congestion at the airport. It was quite interesting to see.

I've been on a lot of flights where speed brakes were used to aid in descent and/or slow the plane in flight. There's a huge difference between using speed brakes in flight and using TR's in flight. The former is not that uncommon, the latter is limited to only a few airplanes.
 
highflyer9790
Posts: 1189
Joined: Thu Jul 07, 2005 1:21 am

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 11:32 am

Speed Brakes are a part of almost every descent, although not always deployed in the full upright position. a lot of times during the top part of the descent (like around FL280-180) spoilers are used to keep the aircraft at a controlable speed while descending at quick rate. they also can be used on finals, etc. On the ground though, they are commonly used to prevent lift and disturb the airflow over the wing.
121
 
ckfred
Posts: 5171
Joined: Wed Apr 25, 2001 12:50 pm

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 12:26 pm

I've heard that 727s landing at DCA on the short runway used to deploy the reverser buckets after reducing the engines to idle, so that pilots could spool up the engines sooner after touching down.

I don't know if this is true. It's just one of those things that I've heard over the years.
 
DeC
Posts: 535
Joined: Mon Aug 15, 2005 5:12 am

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 12:46 pm

Quoting HighFlyer9790 (Reply 41):
Speed Brakes are a part of almost every descent, although not always deployed in the full upright position. a lot of times during the top part of the descent (like around FL280-180) spoilers are used to keep the aircraft at a controlable speed while descending at quick rate. they also can be used on finals, etc. On the ground though, they are commonly used to prevent lift and disturb the airflow over the wing.

And they're not to be deployed at speeds exceeding 300kts, except in an emergency (from what i know).
DEC
 
Jj
Posts: 1189
Joined: Sun Jun 24, 2001 7:40 am

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 1:06 pm

I once read that LAB used to deploy sometimes the 727´s thrust reversers while on descent to La Paz airport due to the high descent rate required to land there...
 
blue787
Posts: 54
Joined: Sun Jun 05, 2005 9:14 pm

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 5:00 pm

I may stand corrected, but I was of the opinion that reverse thrust cannot be activated unless the squat switch is fully depressed.(said switch is on the main bogeys, at least on all 747,it also activates the taxying light.)I therefore believe that reverse thrust cannot be deployed intentionally during flight.Speed brakes (or height dumpers) will really get an aircraft down pretty darn quick,they also assist reverse thrust and brakes on landing.
 
sllevin
Posts: 3314
Joined: Wed Jan 30, 2002 1:57 pm

RE: Reverse Thrust Deployed Before Landing

Sun Nov 27, 2005 5:27 pm

Broadly speaking (the DC-8 being the notable exception) aircraft with fuselage mounted, rear engines have far less disruption if reversers are deployed.

Probably the coolest example is the Gulfstream II that NASA uses as the Shuttle Training Aircraft. It can deploy the buckets with 92% N1. Coupled with spoilers, lowering the main gear, and the modified flaps that are hinged so they can swing upwards as lift dumpers, it can descend at something like 10,000fpm. They literally fly the pattern so that they cross abeam the numbers at 35,000' and then proceed to land.

It requires holding the nose about 20 degrees below the horizon until you get to about 1,500 feet, whereupon you pitch upwards to 1.5 degree glideslope and bleed off airspeed to touchdown.

Steve
 
noelg
Posts: 2313
Joined: Fri Apr 26, 2002 11:39 pm

RE: Reverse Thrust Deployed Before Landing

Mon Nov 28, 2005 6:29 am

Quoting Blue787 (Reply 45):
I was of the opinion that reverse thrust cannot be activated unless the squat switch is fully depressed.(said switch is on the main bogeys, at least on all 747,it also activates the taxying light.)

Whilst this should be the case, but don't forget there are such things as maintenance mods to "get around" this little problem....
 
Lurch
Posts: 721
Joined: Mon Jul 21, 2008 11:54 am

RE: Reverse Thrust Deployed Before Landing

Mon Nov 28, 2005 7:25 am

Concorde could use its reverse thrust on its two Inboard engines only Below MACH1 and at idle thrust only to act as a Form of Speed Brake which Concorde did not have.

No Spoilers ore Airbrakes Slatts ore Flaps on Concorde!
 
A350
Posts: 1074
Joined: Tue Nov 30, 2004 6:40 am

RE: Reverse Thrust Deployed Before Landing

Tue Nov 29, 2005 12:54 am

Quoting SkyHigh777 (Thread starter):
Is this common only to Russian-made aircrafts?

Remember that the thrust reversers at the Il-62 are deployed by the flight engineer. This slows down the process because the pilots and the flight engineer have to communicate. My guess is that the flight engineer just prepares them at idle while the pilot is actually giving thrust a few moments later after touchdown. That would a simple decision: braking - engines 1 and 4, touch and go, engines 2 and 3.

A remark: this slow communication caused the crash of an Interflug Il-62 at SXF in 1989. The a/c suffered an elevator failure after v1 (!). The captain gave order to abort the take-off and deploy thrus reversers. The flight engineer, however, had already locked the reversers by a simple mechanical gimmick to protect them against accidental deployment during flight as prescribed by the checklist since v1 was passed. He didn't believe or understand the order since it was impossible according to the checklist. The captain had to repeat the order, the reversers were deployed very late and the plane overshot the runway. 19 people were killed. Years later, a court found the flight engineer innocent because the accident was mainly caused by the inappropriate design and malfunctioning of the a/c.

A350

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Air to Air Photos taken by airborne photographers of airborne aircraft

Special Paint Schemes Aircraft painted in beautiful and original liveries

Airport Overviews Airport overviews from the air or ground

Tails and Winglets Tail and Winglet closeups with beautiful airline logos