Canadair pushback collision at CPH

[readywhenreaching]

https://pbs.twimg.com/media/CaYijdeWIAAPKwL.jpg
jacdec.de (http://www.jacdec.de/2016/02/04/2016-02-04-sas-crj-900-gear-collapse-on-pushback-at-copenhagen/)
seems the driver was quite lucky to survive..

[SMT Member]

I see jacdec have changed the wording substantially, yet they are nowhere closer to the truth.

The aircraft was performing an engine test in the test cell adjacent to hangar 4/5 in CPH. There were 3 engineers on the flight deck and one on the ground, who's job it was to watch for fires from inside the towing tractor. For unknown reasons the aircraft started moving forward, accelerating very quickly to a speed estimated around 60-70 km/h. The left wing struck the tractor, ejecting the occupant from the vehicle and causing him serious injuries. The aircraft continued forward in the direction of H4, when it entered a left turn. The aircraft eventually pirouetted 360 degrees, resulting in the port wing detaching from the fuselage at the leading edge and the port MLG getting push aft and inwards, embedding itself half-way inside the fuselage.

The occupant of the tractor is intensive care, in a medically induced coma, fighting for his life. Late 20s of age, with a pregnant girlfriend.

[JammedStab]

I see jacdec have changed the wording substantially, yet they are nowhere closer to the truth.

The aircraft was performing an engine test in the test cell adjacent to hangar 4/5 in CPH. There were 3 engineers on the flight deck and one on the ground, who's job it was to watch for fires from inside the towing tractor. For unknown reasons the aircraft started moving forward, accelerating very quickly to a speed estimated around 60-70 km/h. The left wing struck the tractor, ejecting the occupant from the vehicle and causing him serious injuries. The aircraft continued forward in the direction of H4, when it entered a left turn. The aircraft eventually pirouetted 360 degrees, resulting in the port wing detaching from the fuselage at the leading edge and the port MLG getting push aft and inwards, embedding itself half-way inside the fuselage.

Thanks for the update. I was wondering how a pushback would have been able to end up like this. There seems to have been a long list of maintenance runs gone awry with the plane moving forward unintentionally such as the A340 in Toulouse over a wall, an A310 in Vancouver into a hangar and this one and no doubt others. Something to think about if ever in a situation where you are in front of an aircraft during a high power engine run.

[captplaystation]

At the risk of incurring the wrath of a fine body of men (Engineers ) is there a case for having a qualified pilot in the Cockpit for anything more than an idle thrust run up ? (Ducks for cover from flying spanners etc :ooh: )



Edited to say, I don't know the exact protocol for these exercises, and hope that 1 of the 3 has one responsibility only "the brake man/systems man " there to cut the power if circumstances dictate, there also to assure that systems critical to control (thinking hyd/brake systems being pressurised etc ) are functional / available.

Sorry if this comes across as teaching yer granny to suck eggs, but is there a "checklist/procedure" that SHOULD have prevented this happening ?

[chuks]

I have a German friend who works on large aircraft as an engineer. He once told me that he had been checked out to do ground runs, and I think he mentioned that he was checked out to taxi aircraft as well.

It's not rocket science, so that I don't see why an engineer should not be just as safe as a pilot when it comes to doing ground runs. Perhaps even safer, if the engineer routinely does ground runs when a typical pilot might only do one now and then.

It might be that there was a failure to chock the aircraft, something of that nature, that led to this accident. I guess we need to wait for the report to find out about that.

[CEJM]

Captplaystation.

There is no case for having a pilot on the flight deck when doing an engine run above idle power. I would even go as far to say that the engineers are better trained to deal with these situations then the pilots are. (Ducks for cover from flying flight cases!). How often do we as pilots perform an engine run at max power for several minutes with the brakes on?

Normally when we (pilots) perform a max thrust take-off we are staring down a nice 'long' runway. If something goes wrong (i.e. Brake failure) then we got a reasonable time period to react.

If the engineers perform a max thrust engine run then this is often done in the engine test bay which is sometimes open at the front or, as at some noise sensitive airports, is completely enclosed. Hence, the time to react is a lot shorter.

Before I started flying I worked as an engineer and performed engine runs on a near daily basis, from idle runs to the less frequent high power runs. Every year we had a sim session to train for emergencies and the aircraft jumping its chocks etc was part of this. However I am not sure if this was a regulatory requirement or just a company requirement.

Procedures and checklists are in place to mitigate against any problems. But very similar to pilots, the engineers also face time pressure. Especially when an aircraft is taken out of service in the middle of a series of flights. Not saying at all that this contributed to this accident but as with anything there is a chance that corners get cut when under time pressure.

[His dudeness]

The occupant of the tractor is intensive care, in a medically induced coma, fighting for his life.

Hope he survives and recovers. That must be a terrible few seconds when you realize the jet coming at you and you can´t do anything about it.

I don't see why an engineer should not be just as safe as a pilot when it comes to doing ground runs. Perhaps even safer, if the engineer routinely does ground runs when a typical pilot might only do one now and then.

+ 1

[framer]

When I was on the spanners I used to do high power engine runs.
Now I'm a pilot and I don't.
My personal opinion is that the Engineers are probably as safe if not safer than the pilots for this particular job purely because of recieving training in this particular job.
Every now and then we get a c0ck up with an airborne situation, every now and then we get a c0ck up with a ground based situation. Such is Human failability. The only panacea is to be conservative in how you operate, be it on the ground or in the air.

[Capn Bloggs]

I would predict that a pilot would be far more likely to make an instant, snap decision to chop the throttles if something went crazy, due to his/her extensive time actually operating the aeroplane doing all sorts of things which would significantly reduce the startle effect, as well as Sim training which would put them on a far higher/quicker reaction level than any engineer could be.

I would even go as far to say that the engineers are better trained to deal with these situations then the pilots are. (Ducks for cover from flying flight cases!).
What's the Sim program/recurrency for engineer ground-run courses? If there isn't one, IMO it is highly unlikely an engineer could be better than a pilot at handling an incident.

And no, I'm not suggesting engineers are lesser persons than us pilots. Framer has proved that! :)

[oliver2002]

Taxi tests and high power engine runs prior to delivery are done by technicians at Airbus, even for A380s. The people doing this are at all times alert with the 'PF' with a hand on the throttle and ready to respond while the 'PNF' is running checklists to verify everything they are testing. A widebody gets quite agitated when in the testing stand on full throttle. Especially after the A346 incident in TLS all the testing crews absolutely know what to do if certain things happen, they are trained for it. A regular 'pilot' wouldn't know more or less.

[falcon12]

Like framer, I too when on the spanners, did full power ground runs - at LGW. Starting from the east end, taxing to the run up bay at the west end. Getting back sometimes involved entering the main runway, unlocking the flight controls, adding power and taxing back, quickly. The need for a pilot to do it was never mentioned in those days.

The golden rule on any power runs, wherever you do them is, in the event of sudden aircraft movements, shut the throttle immediately and stand on the brakes. It seems that did not happen at CPH.

Just hope the guy in the tractor recovers.

[wrenchalot]

There are situations pilots will not encounter, but are encountered by maint. personel.
I can think of at least 3 of them, that could have led to this accident.
One is to make sure the ADG squibb will fire after loosing the last generator( in the air).
The procedure was to disconnect the squibb connector, and hook it up to another connector with a 15ma fuse.
After starting the engines and APU, the weight- on- wheel breakers were pulled, then the gen. switched off one at the time; the fuse would blow after the last gen. failed. You have to realise, the brakes will go off with WOW.
Another test was to make sure the ACU would go to "HIGH" mode if the other failed "in the air". This required a similar procedure.

A third, is to make sure the ground spoilers (once deployed) will snap shut when the throttles are advanced above idle, again "in the air". This one was brought out following the crash of a DC-8, in Toronto, in 1970, where the ground spoilers did not retract during a touch-and-go scenario.
Of course, this test is usually done in the hangar, but nothing stops you from doing during a run-up, along with a number of other tests following a maint. check or simply a repair to a system.
Following a check list is fine ( step 1: apply parking brakes) when everything is serviceable and all the breakers are "in", like a pilot going to fly.

Maint. tests are often done with some breakers pulled, on systems still being worked on, making it difficult to "find" them in a panic situation.
Of course, I'm speculating until more is known, but I suspect one of these scenario was being performed, not realising the brakes would be released while WOW, and when they realised they were moving, they would have stepped on the brakes as the first reaction, then panic, then if they realised the breakers were pulled, find them and push them in; by then, they're moving...

As for safety procedures, that tractor should have been nowhere near in front of the a/c;that's an absolute no-no; it is to be parked well away from the a/c, and to the side of it; there should never be anyone standing in front of a running engine: to the side and well clear of the wing, with the a/c in his sight at all times.
Lastly, when performing testing similar to the above mentioned, we always carried a heavy rubber set of chucks with us before leaving the hangar.
The old phrase: There is never time to do it right, but there's always time to do it twice.
I also realise some of these checks may have been modified or discontinued by now, but I did lots of them, always requiring total concentration.

[dbbass]

In order to avoid this Kind of situations We do have in maintenance some safety nets.
Every 2 to 3 years depending on the company, there is a Simulator cession with all the Problems you can Encounter during a run.


But above all, even if you pulled tons of CB's, you have checklists for running high power, AMM procedures and again tons of warning as preamble of any maintenance Operation,( particularly when chapter 70 to 79 is involved).
There are safety precautions you should not even think about shortcutting like chocks, park brake, or if no park brake Holding the Brakes (mandatory on Airbus as parking brake cannot hold hign power).
On some aircraft you have to put the EDP on (not automatic) and electric pumps as back up...


I did hours and hours of high power run on prop and jets aircraft.. You have to Think and use checklists, it is so easy to Forget something.. And the stress is 99.9% seft induced, never in my carreer a Boss told me to not use checklist or make shortcuts to go faster.
But I believe I would be very upset if I would be the Boss of the guys in CPH...


You know in the past there was nothing, and after a few in/accidenst the authorities came with rules and procedures. They are always People thinking they are better than the others, but These rules are really helpful that you can oppose them in case of time pressure from you Boss...
And they can save lives and aircrafts...