If a reverser is U/S and MEL'd, isn't it physically locked out so it can't deploy?

That has to be safer than a reverser that isn't locked out?

The MD-82 has an over-center locking mechanism, in addition to a latch, so it would require failure of two items to deploy un-commanded.

ECAM Actions.

philpat

if your dad said the wellington was the last pilot's airliner, you might be misquoting him.

back to the thread.

a locked out thrust reverser should be quite safe, provided the proper "locking out" actions were done.

thrust reversers are usually very safe and very , very useful for many aspects of ground handling of aircraft.

Unexpected ThRev Yaw X Roll
 

Discussion from a few slots earlier:
"... any accidents caused by a faulty Thrust Reverser that had been MEL'd?..."

I couldn't recall any on the DC-9/MD80. But this B717 pilot claimed that the B717 (shorter/ lesser "Tail Volume") BMW-engine's ThRev dealt him a rapid Yaw X Roll upset:

Incident occurred Monday, 19Feb01 , Milwaukee, WI
Aircraft: Boeing 717-231, registration: N2410W
Injuries: 67 Uninjured.
[Recent = Probable Cause Approval Date: 3/30/04]
CHI01IA124
http://www.ntsb.gov/ntsb/brief.asp?ev_id=20010427X00832&key=1
The MD80 sim' suggested to me that control was OK during flight with the ThRev DEPLOYED (but that was the Sim').

Privately, I recorded these comments from that B717-pilot's S&C observations during that mishap-flight with the Buckets Deployed:

Sorry to be harsh, but this is a "Professional Pilots' Forum". Unless you have actually studied and understood the applicable accident reports, and their recommendations, then proposing actions such as you do is about as logical as banning all takeoffs worldwide from RW36 because that was what the Spanair took off from :{

Thrust Reversers are useful, but rarely vital. They have numerous safety / indication systems to avoid the odd accident caused by a Thrust Reverser. Any unservicability with these systems - and surely it is far better to just lock the system out, and await a timely analysis engineering solution?

A knee jerk reaction to just "ban Thr Rev U/S under MEL" will lead to a lot of p***ed off Pax stuck around the world, and pressure to continue flying with a "slightly dodgy Reverser", or hasty, maybe inappropriate rectification to "clear" the fault. Invariably I would prefer to operate with an MEL'd Rev U/S (and locked out) than one I had the slightest concern about...

NoD

IGh...

Thanks for that, re the 717. Hard to cater for (any) incorrectly applied Maint procedures :ooh: On the B757/767 and A320 series, the lock out pins / whatever are clear to the Flt Crew on the walkround... less obvious maybe on other types, particularly with engines mounted about your level. That said, the error you relate might not even be as simply seen as "pins in place"?

NoD

The time to talk about corrective actions is when the cause is known.

A lot of folks were talking about engine failures, non-containments, and what's wrong with engines in general. then they started talking about flaps and slats and when they couldn't agree on whether they were deployed or not they start talking about reversers and even though there is no agreement on whether they are deployed or not some are already proposing corrective actions without any comparative data.

I will say it again everything that man designs or builds will break, some more often than others. For crying out loud how do you fix something that hasn't broke? You're just liable to screw it up even worse.

Let's get back to arguing about what's broke before we try to fix it and that goes for crew error suppositions as well.

I used to have a big sign on my office door

"all ye who enter bring data"

Then we could decide how to fix it

Sorry lomapaseo, I don't bring data, but just enquire some 12 days I believe after the original accident has there been any worthwhile statement or initial report from the Spanish authorities?

It is so easy to sit back and say nothing while other similar aircraft carry on flying.

Well said, no further comments.


Green-dot

YouTube - Conversacion entre Spainair y Barajas antes del accidente

Resume in english

From Spanair Coordinator to Barajas:

as JKK5022 come back to the gates request to change the registration to HFS (EC-HFS) and delay slot to 1235Z

The Spanair coordinator also request stand C49 to deboard if finally is necesary

the JK5025 also change the registration to HFS in arrival to madrid from Gran Canaria (this is the return flight for JKK5022

At the end of this call, Barajas request a confirmation call for these changes after maintenance service confirm the problem (30 minutes on ground, enter the technicians and disconect the RAM sensor breaker, about manual, 10 days inop is GO)

In the secon call Spanair request undo the changes and put again as registration in the flight plan HFP (EC-HFP) to JK5022 and JK2025
and confirm the slot to 1235Z

The trith call is from Barajas Emergency service to Madrid Fireman service to coordinate the emergency plan

TR deploying before n/w ground contact
 

YouTube - MD-82 SAS landing EHAM

SAS MD 82 landing at EHAM deploying TR before n/g weight on wheel

Since when is TEN DAYS 'timely' ? Seriously what excuse can there be for that other than saving a few pence ? Especially considering how they can be so deadly.

The pictures show ONE deployed reverser. Maybe having both of them working might just have helped a little bit ?

Reverser
 

Ecam:
Hi.
the T/R deployment is procedurally delayed on the MD-80 until nose wheel touchdown to avoid ground contact from the lower reverser buckets.
regards

all ye who enter, bring data
would have been an instruction to deliver information. Without the comma it is a statement, perhaps emphasising your powers of observation.

A long time ago an MD82 crashed at Madrid but even with CVR's and FDR's recovered nobody knows what happened. Why?

Maybe it is time to release this information to the public.

We frequently have a Thr Rev U/S for 10 days - it is the allowable period, and as you say, pennies count, so most defects do not get cured for much or all of the allowable period. Fact of life... not ideal.. but here we go.

How are they "so deadly" :ugh: They are rarely "required" in Performance Terms, and when "locked out" (correctly) somewhat less deadly than being available ;)

NoD

B717 T/R deployment
 

Nigel, in that case, the 717 T/R lockout pins were not installed correctly. If maintenance does it wrong (as they did then), crews can still detect it during their preflight (pins are obvious, red painted and protrude when installed correctly in the B717 as well as some other types as you relate). I do not know about the MD8x.

Manrow re 1st Board Report
 

Manrow, as far as I am aware, there has been only one official reporting on facts by the Investigation Board, as reported by myself on post #1020 in page #51

Another factual report is expected late September.

If they had remained on the runway... maybe.
Off the tarmac, involving a tailstrike, bouncing heavily, there is high risk that a bucket hits the ground and separates from the engine, causing the intended reverse thrust to become forward thrust :uhoh:
IMHO safer to use brakes, and spoilers to put weight on the mains.

So if thrust reverse NEEDS to be used for WHATEVER reason, what's the effect of having it work on one side only ?