Just curious, was on a 738, runway BA was poor from reading the PIREPS and on landing, the thrust reverses were kept on, to about 20kts per my phone until we came to a full stop then proceeded with a taxi. Wish I recorded it

My procedures are 60 kias. It loses its effectiveness the slower you are going.

Our procedure on the 330 and 350 is idle reverse only below 70 knots. As Redbellyguppy says it is less effective at lower speed. However in an emergency you can keep it on until you stop.

And it might not be very good for the engine as at slower speeds it will start to ingest the dust, that is raised by the reverse thrust.

alaskan9974 wrote:

Just curious, was on a 738, runway BA was poor from reading the PIREPS and on landing, the thrust reverses were kept on, to about 20kts per my phone until we came to a full stop then proceeded with a taxi. Wish I recorded it

Just to clarify, if the RCR was poor, unless BA is very different from other airlines I Have been involved with, they would not have been able to land. Generally TWR will ask a proceeding aircraft for a braking action report. If it's poor, you will instantly hear quite a few diversions start.

I agree with the other answers, every aircraft I have flown with reverse, you had to be coming towards idle reverse at 80 knots, and in idle reverse at 60knots. Below 60 knots there is virtually no added effect in braking. Also, as a general statement, once reverse is stowed, they can't be used to slow down while taxiing.

Thanks. It was at an uncontrolled field, I was just surprised to see the reverse on to such a slow speed, we made a full stop before we backtaxi'd. Was a little strange to see the life raft panels open in the aisles. I will say the snow dust kicked up was a sight to see I wish I snapped a picture but most windows in the front were covered up anyway from it.

alaskan9974 wrote:

Was a little strange to see the life raft panels open in the aisles.

Am I reading this sentence incorrectly? Why would life raft panels open in the aisles?

How long is this runway?

vikkyvik wrote:

alaskan9974 wrote:

Was a little strange to see the life raft panels open in the aisles.

Am I reading this sentence incorrectly? Why would life raft panels open in the aisles?

How long is this runway?

I'm guessing from the jarring on landing helped to shake them loose? Just a guess on my part, I have no experience with their function. Runway is just under 6k ft. Almost felt as though it was a bit of back and forth between braking and skidding.

Thanks for the replies, with the reverse on at a slower then normal speed, would that allow exhaust fumes and haze in the cabin?

alaskan9974 wrote:

vikkyvik wrote:

alaskan9974 wrote:

Was a little strange to see the life raft panels open in the aisles.

Am I reading this sentence incorrectly? Why would life raft panels open in the aisles?

How long is this runway?

I'm guessing from the jarring on landing helped to shake them loose? Just a guess on my part, I have no experience with their function. Runway is just under 6k ft. Almost felt as though it was a bit of back and forth between braking and skidding.

Thanks for the replies, with the reverse on at a slower then normal speed, would that allow exhaust fumes and haze in the cabin?

Fumes could. Cabin air comes from the engine bleeds. If exhaust is re-ingested by the intake it can make its way into the bleeds. I don't think you'd get haze as a consequence since bigger particles might not make it all the way, if you will.

alaskan9974 wrote:

Minimum speed for reverse ?

There is none, the only limit normally for high bypass engines is the reverse thrust cannot be used to reverse the aircraft.

zeke wrote:

alaskan9974 wrote:

Minimum speed for reverse ?

There is none, the only limit normally for high bypass engines is the reverse thrust cannot be used to reverse the aircraft.

The C-17 disagrees with you wholeheartedly. Was stationed at McChord for almost 6 years. Now they don't do it stateside (besides airshows) but when deployed, they always backed out of the spots at Al Udied.

And yes I know the P&W engines on the C-17 have core engine thrust reverse as well, but it's still a high bypass.

Andre3K wrote:

zeke wrote:

alaskan9974 wrote:

Minimum speed for reverse ?

There is none, the only limit normally for high bypass engines is the reverse thrust cannot be used to reverse the aircraft.

The C-17 disagrees with you wholeheartedly. Was stationed at McChord for almost 6 years. Now they don't do it stateside (besides airshows) but when deployed, they always backed out of the spots at Al Udied.

And yes I know the P&W engines on the C-17 have core engine thrust reverse as well, but it's still a high bypass.

I've also seen Air Tran 717's powerback from the gate in ATL.

Andre3K wrote:

The C-17 disagrees with you wholeheartedly. Was stationed at McChord for almost 6 years. Now they don't do it stateside (besides airshows) but when deployed, they always backed out of the spots at Al Udied.

And yes I know the P&W engines on the C-17 have core engine thrust reverse as well, but it's still a high bypass.

The C17 is an irrelevant military application to the discussion on civil aircraft, they can also select reverse in flight.

Look at civil aircraft 737, 777, 747 etc reverse is prohibited limit for reversing an aircraft.

In case you missed it the OP was referring to the 737.

TWA772LR wrote:

I've also seen Air Tran 717's powerback from the gate in ATL.

That is due to the clamshell reverse, typically high bypass engines use a translating sleeve or blocker doors which which only diverts bypass air.

zeke wrote:

There is none, the only limit normally for high bypass engines is the reverse thrust cannot be used to reverse the aircraft.

The only reasonable exception to that would likely be the 757 or the L1011. Eastern used to powerback both.

But I agree, there are very few commercial jet transport aircraft certified in the last 30 years where it is allowed. In my opinion, it is not due to lack of capability of the engine, but with powerbacks no longer being used, it would make sense that the airframe manufacturer would no longer test and certify such a manoeuvre.

zeke wrote:

The C17 is an irrelevant military application to the discussion on civil aircraft, they can also select reverse in flight.

Look at civil aircraft 737, 777, 747 etc reverse is prohibited limit for reversing an aircraft.

In case you missed it the OP was referring to the 737.

Check out the post above this reply.

EA B727s powered back. I once backed up on the Inner at KBOS when the taxi clearance got us pointed at an outbound 727. The plane will back up, legal issue is something else.

The C-5 could back up at lightweights, but not certified for it. I landed on an RCR 05, we had distance by RCR, but extremely poor it was. Charted landing distance was 5,000’, with reverse on until nearly stopped, we were right at the 2,000’ remaining board on a 7,000’ runway

GF

zeke wrote:

alaskan9974 wrote:

Minimum speed for reverse ?

There is none, the only limit normally for high bypass engines is the reverse thrust cannot be used to reverse the aircraft.

It look ok not to have an Speed for Reverse use. When it’s necessary to brake at any cost.....
That said, if Reverse is used below 60kntos (valor deffer for each engine or engine- airplane combination)’ a phenom call “ Gas Reingestion” take place.
Trying to describe the simple way, gas that exhaust the reverse doors, been redirected and having more speed that the airplane, will go to engine fan. Upper part of engine’s gas will give not problem, but the gas that leave th reverse directed to the landing strip, will sweep all stones around into engine’s fan, and....
Crew should open an item in Log Book about Reverse used with an a/c speed < of x knots, and this will trigger a long mx event in wich all engines have to pass a dedicated inspection that includes boroscope’s inspection and....

Rgds

Apprentice wrote:

It look ok not to have an Speed for Reverse use. When it’s necessary to brake at any cost.....

Rgds

Interesting take. Would love to be a fly on the wall when the crew has to explain why the aircraft is on it's tail! Every underwing aircraft I have ever flown which had TRs, there was a very big prohibition about using reverse thrust to slow down. You don't do it. End of story. Note, I am not talking about tail mounted engines like the 727 or DC9, etc.

The whole thing about aviation is you never leave yourself just one option. I don't care if it's on the ground or in the air. Good airmanship is planning ahead and giving yourself options. I have had my aviation career for over 50 years and that was the thing which was drilled into my head in both civilian and military training.

longhauler wrote:

The only reasonable exception to that would likely be the 757 or the L1011. Eastern used to powerback both.

It is not standard on the 757, I think it’s just the 200 with one engine manufacturer. I would need to check the manuals when I get home.

As for the L1011, next time I see one of those or a Convair 880/990 at a gate I will know they can power back. Hardly relevant today.

mmo, Hi: Commercial aviation is not a written science.On december 21, 1999 a Cubana DC-10 landing at GUA, found not enough landing strip to brake. Plane went out of strip and fell down. Been a Fly would not be of help, no one from the cockpit survived to be debriefed.
All three reverses were opened all the way, 2 brakes burn the overtemp indicators. Still nobody asked at that time why Crew keep reversers on and engine a full reversing power....
Rgds

zeke wrote:

longhauler wrote:

The only reasonable exception to that would likely be the 757 or the L1011. Eastern used to powerback both.

It is not standard on the 757, I think it’s just the 200 with one engine manufacturer. I would need to check the manuals when I get home.

As for the L1011, next time I see one of those or a Convair 880/990 at a gate I will know they can power back. Hardly relevant today.

In reality, nothing is relevant today, as no one is doing powerbacks. But, that's the point I was making.

Back in the days when airlines flew massive hub/wave operations there was a financial case for powerbacks. Airlines like AA, EA and NW would see the need for a hundred costly tugs for about 20 minutes, then sit idle for three hours. Far cheaper to only purchase a quarter of the tugs and powerback the rest.

Starting with the clamshell type reversers, the need spread to high bypass ratio engines with only fan reverse. EA was the first with the 757 and the L1011. So it is likely the reason high bypass engines are not doing powerbacks is not because they can't, as I have shown, they can. The reason is that no one sees a need any more and airframe manufacturers won't go through the testing/certifying process if there is no need.

You correctly state that only one engine manufacturer for the 757 was certified. Again, not because they can't, but because EA was the only one doing powerbacks with their 757, and they had RR engines. Same thing with the -300, no one wanted it .... not certified. If a business case could be made for it today, likely the testing/certifying process would start.

For the record, looking at the AAL CV990A manual in my library, those aft fans were not certified for powerbacks! The DAL CV880 manual does not state either way.

Apprentice wrote:

mmo, Hi: Commercial aviation is not a written science.On december 21, 1999 a Cubana DC-10 landing at GUA, found not enough landing strip to brake. Plane went out of strip and fell down. Been a Fly would not be of help, no one from the cockpit survived to be debriefed.
All three reverses were opened all the way, 2 brakes burn the overtemp indicators. Still nobody asked at that time why Crew keep reversers on and engine a full reversing power....
Rgds

IIRC, the cause of the accident was a long touchdown on a wet runway and failure to execute a go around. That aircraft was doomed it made no difference if the aircraft went off with full reverse or takeoff thrust set. It was going off the runway no matter what. So, I don't know what your point is. My point was about not putting yourself in a situation just like that. You always should have a option, such as in this case a go around or missed due to a non-stabilized approach.

Crew never had landed a plane in GUA, they didn’t know strip’s characteristics. At this time, ten signs with numbers were an indication of how much strip distance remain ahead, but this was a particularity of this strip, not commom for them. They only recognized that strip was about to end some 500 mts and just tried to stop the plane and turn it. In this Stop maneuvring, Reverses were used until final moment. And this is my point, if deemed necessary, no reason to do not use reverse just because speed is, let’s say 50knts

Apprentice wrote:

Crew never had landed a plane in GUA, they didn’t know strip’s characteristics. At this time, ten signs with numbers were an indication of how much strip distance remain ahead, but this was a particularity of this strip, not commom for them. They only recognized that strip was about to end some 500 mts and just tried to stop the plane and turn it. In this Stop maneuvring, Reverses were used until final moment. And this is my point, if deemed necessary, no reason to do not use reverse just because speed is, let’s say 50knts

I don't want to keep going round and round, but the fact is they screwed up big time! I have been into loads of airports where I had never been there before and managed to survive. The basic cause was an unstabilized approach which resulted in a long landing. The crew should have executed a missed approach and that's the end of the story. Pilots fly into many airports for the first time and that is no excuse.

We have arrived: Crew’s Fault.

Back to theme, below some speed, gas reingestion by fan, including some fod is higly possible when a/c is at low speed.
Rgds

60 kts. on E145

Off topic but if there was a total brake failure on a big boy plane (lets say A320) how long would it take to stop using only TRs, I know it's highly unlikely but I'm curious none the less.

Fred

Distance Remaining boards on the left of both sides are pretty common and great aids. I always used them when installed.

GF

flipdewaf wrote:

Off topic but if there was a total brake failure on a big boy plane (lets say A320) how long would it take to stop using only TRs, I know it's highly unlikely but I'm curious none the less.

Fred

Its done frequently at DFW, landing on 17C with just idle reverse and no brake usage, the aircraft (a320) is below 20kts by the time you reach the M7 high speed taxiway and turn off. (as long as it's coordinated with tower and they approve it) Idle reverse can be used all the way down to a stop as long as it's stowed before you leave the runway. The first time brakes are used is for the turn onto A/B to hold short of 17R.

Technically, it can be used at 0 knots too, you just won't see much of an effect. I've had crews use it more than once on CRJ aircraft when using a strap capture towbarless pushback that had the strap get stuck. The reverse thrust takes just enough pressure off the nose gear to give the strap some wiggle room.