Noticed today that the NTSB issued a report on the recent incident with an AmericaWest A320 at PHX a few weeks ago. The aeroplane left the side of the runway and the nose gear collapsed. According to the report, a thrust reverser was locked out and the crew used reverse on the other engine after touchdown.
What are your airlines procedures in this case? As I have flown only 3/4 engine jets, a locked out reverser does not present too much of a problem, provided caution is used.
Which brings us to the point of the previous several posts (which I have just deleted).
There are other Forums within PPRunNe where colourful personalities might be appropriate and intemperate comment tolerated.
However, I think that most of us would prefer to see Tech Log steer a rather more serious course in the water..... the powers that be at the top of the food chain have, in fact, so directed.
If the moderators of this Forum see any significant increase in intemperate or blatantly inappropriate posts, we will have no hesitation in deleting them in the first instance and, if necessary, removing the ability of the originator to participate in this Forum.
Please keep it polite and pleasant, people.
Now, 411A has made a perfectly reasoned and interesting post. Perhaps someone might be moved to venture an answer ?
Last edited by john_tullamarine : 18th September 2002 at 13:53.
411A I have flown B737/757 and 767 and in each case, with the companies I worked for, if one reverser was locked out then the rule was 'no reversers to be used except in extreme emergency, then with upmost care'. Since all landing data is predicated without the use of reversers it did not present a problem on those aircraft.
Well you can land with one failed and still use reverse on the other. You can have an engine fail prior to V1 and still use reverse on the other.
The over-riding principle is to use reverse to 'the limits of directional control' ans back off if necessary.
Having said all that, if one is locked out for tech reasons, do not use reverse for the landing. As previously stated, all landing perf is factored for no reverse anyway - it just means the brakes do more work to achieve the same decel rate selected on autobrake.
MEL: ..... One or both may be inoperative provided: 1) the inoperative reverser is deactivated and secured in the stowed position, and no operation or procedure is predicated on thrust reverse use,....
Crew Operating Procedure: .... At landing: It is recommended not to select reverse thrust on the AFFECTED engine......
No further restrictions to be found.
The only restriction on assymetric reverse thrust I could find was the following (all in one engine out ops, which can be compared for aircraft handling purposes)
LANDING ONE ENGINE OUT A321 ONLY: For automatic rollout the use of remaining thrust reverser is limited to IDLE REVERSE.
So basically, operating under normal conditions, I am only performace restricted in cases that require reverse thrust.
Considering aircraft handling, the FCOM simply states: -Initially apply idle reverse -Depending on situation and runway conditions increase reverse stepwise.
I have personally experienced a landing where one reverser failed to open, and had absolutely no problems in directional control. So cases with the limitation already known should be even easier to handle, as the slight yaw moment doesn't take you by surprise.
A cogent case can be made for a company's implementation of MEL procedures to require an extra small factor on the required landing distance for an intentional dispatch with U/S reversers to provide something approximating the same risk level as would apply with functioning thrusters. Same for the ASD case.
Can recall at a previous company that operated wide-body three engine jets, the use of reverse (with one locked out) was not restricted at all...until the respective fleet manager got rather off to the side/end of the runway (and in the dirt) one day and then, just for a good show, tried to get back onto the runway using full reverse (on two) with spectacular results. The tower supervisor told me later that the huge dust cloud could be seen for miles.
I have been off the 320 for 2.4 years now but we routinely used full reverse on 1 engine if one was locked out.
IT was not a problem at all, hardly any yawing motion on that aircraft, but the CFM engines just make a lot of noise on the ground anyway to let the pax know we have landed.
I have had one T/R inop many times on the 737 and had no problems using reverse on the one side.
I did see the skid marks on Rwy 8 at PHX. They started from the centerline and turned to the right towards a high-speed. He missed all the lights and plow through the dirt next to the runway. You could see a white outline of the aircraft where they stopped. Kind of like a police crime scene.
Anyways...I've had reversers locked on 737, L-1011 and 777. Generally, there were no restrictions, other than what was in a company FOM that stated that an aircraft with a locked reverser could fly, but no reverse selected on a wet runway. Remember that all certification is done without reverser performance, so having a reverser is just a bonus.
Airmanship dictates that...don't use just one on a slippery runway, or ....one can get a full 360 degree look at the airport enviornment.
I believe the location of engines plays a role, too. Looking into my C-560/525 notes, I cannot find any restriction on single engine TR use (it is late, however, and I had a few beers) It would be interesting to compare tail-mounted engine aircraft procedures (F100, MD80) to the standard under the wing mounted engine plane procs (Airbus and Boeing, err except the 717 )
With the aft fuselage engines, even the inop engine's reverser buckets are supposed to create a bit of drag, and maybe the difference in drag could never be as much as with wing-mounted engines?
Also, they say that an engine failure in an A-320 at V1 or higher etc creates little opposite rudder input required (by the pilot). When you land the 320 with one inop reverser, or with it somehow open on a failed engine, do the flight control computers limit the yaw tendency in this case, as with a failure on takeoff etc?
Those FCCs will certainly remain a 'mystery to me' for a while. Hey, that phrase sounds like the title of an old Fleetwood Mac album, in the days when "we didn't need no stinkin' " l@ser beams to play a song, and no ACARS to check our max landing weight for each and every landing. That weight might be ok IF you do a max-effort landing: bam!.
With an engine out or reverser out on the 747, we would brief inboards only or outboards only for reverse on landing. However, the asymmetric operating engine reverse would still be selected to idle only.
'Asymmetrical reverse thrust may be used with one enhine inop. Use normal reversing techniques and procedures. If it appears that rudder authority is becoming limited during deceleration, return the lever to the reverse idle detent'
If Boeing say you can do it, then it must be ok. I agree that if you were at x-wind limits on the wrong side, then rudder authority could become limiting. I've used it several times, and noticed no swing, plus always use it with one engine inop. in the sim.
Our performance manuals state that with one or both reversers inop, the LDR increases by 6%, and the RTOW by 750kg (dry), 1400kg (wet). Also, for wet rwy performance, engine out reverse thrust is assumed.
You say you wouldn't use assymetric reverse for landing, but you all brief to use it for an RTO every day! If an engine fails below V1, you close the thrust levers, select the speedbrake and deploy max reverse thrust on the operating engine.
Have landed an A319 several times with a thrust reverser locked out and idle reverse on the other engine. No discernible difference in handling quality whatsoever. Our Ops Manual has no restrictions for the one T/R inop case other than idle reverse thrust only.
At Cape Town last year, a new captain to the line had a new (like just out of the box!!) ERJ 135 and misjudged the turning circle on a taxiway and put one leg in the dirt.
As he still had the other main and the nose on the tarmac, he decided not to wait for the tow truck and 'sand' plates.... in due course they arrived with the tow-truck and the 'sand' plates to get him out.
When I went through (two weeks later) the grass and dirt was still showing the results of his experiment with two rather powerful donkeys ....
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