automation...civilian vs military attitudes

[NutLoose]

I'm not sure whether it was that DeathStar, or the one the ground crew tried to set on fire by holding in a reluctant CB, destroying most of the wiring,

I will add that it was a BA engineer that did that, not an RAF one.

[TorqueOfTheDevil]

Very good article.

Agreed - fascinating and terrifying.

It would appear that the problems were correctly diagnosed, both the loss of airspeed info and the subsequent stall

Are you sure? They were certainly aware they were descending rapidly, but my understanding of the chatter in the cockpit suggested that they felt the aircraft/autopilot was malfunctioning/failing to react to their inputs, rather than it had simply stalled (and the aircraft's own attempts to communicate the problem were lost in the general confusion). Unless I missed something, none of the three pilots mentioned a stall, let alone the recovery action.

[[email protected]]

TOTD you are right - I read this

Carried by inertia, the airplane continued to climb. A flight attendant called onto the intercom, apparently in response to Robert, who may unintentionally have rung her while trying to rouse the captain. She said, “Hello?” As if the buffet weren’t enough of an indication, the stall warning erupted again, alternating between STALL STALL STALL and a chirping sound. The warnings sounded continuously for the next 54 seconds.

The flight attendant said, “Yes?”

Robert ignored her. He may have realized that they had stalled, but he did not say, “We’ve stalled.” To Bonin he said, “Especially try to touch the lateral controls as little as possible.” This is a minor part of stall recovery, and nothing compared with lowering the nose.

and clearly thought to myself no trained pilot could miss those cues - evidently I was wrong!

[TheChitterneFlyer]

[Quote] The first words on the CVR after the crash-and-go were "It shouldn't have done that..... [Unquote].


That particular incident was when a "Training Captain" was conducting a demonstration/familiarisation sortie with the Station Commander in the other seat. At that time "Autoland" wasn't an approved manoeuvre for the RAF and crews only had scant information of how the system worked. Hence, with little experience of how to set up the initial approach for "capture" of the LOC and GS, the Training Captain engaged A/L during the final approach in an attempt to demonstrate, i.e. "show-off", the capability of the aeroplane. At 300 feet they had the wrong perception that the autopilot had captured the GS, and the LOC, when in fact it was in CWS mode. The autopilot, at the last moment, captured the GS and took a dirty dive to capture the GS which resulted in a high ROD "into" the runway. The resulting "bounce" was recovered into a Go-Around which, indeed, had ruptured the Centre Tank which contained ballast fuel for the training sortie. The main wing spar had also taken a huge impact load and they (the crew) were very lucky to get away with a successful landing.


As is always the case with a new aircraft on RAF inventory, someone must be nominated as a "Training Captain"! The said pilot was a very experienced Victor pilot with many hours under his belt, though, he was very inexperienced on the TriStar.


The "bottom line" was... the lack of understanding of the Autoland System and little experience on type.


As a separate aside reference the "Circuit Breaker" incident (the brake "Top up Pump" power supply); the BA Ground Engineer held-in the CB in an attempt to get enough hydraulic pressure to tow the aeroplane... which set fire to the hydraulic pump (and the whole of the hydraulic bay). During the extensive repair programme it was discovered that a previous (undocumented) repair had been carried out to the Main Spar. Hence, the return to flight of this particular (ex PAN-AM) aeroplane took longer than expected.


As is always the case on PPrune, posters don't always get the facts correct. The crew of the TriStar Autoland incident didn't sit back and watch the aeroplane fly into the ground, it happened in very quick time at a very low altitude when they (the crew) hadn't seen that CWS Mode was temporarily engaged whilst the Autopilot was trying to look for a valid GS/LOC signal. The aeroplane was flying at a normal ROD for the final approach, albeit in CWS Mode, when, during the final 200 feet or so, Autoland found the GS signal and the autopilot made a rapid descent correction... and struck the runway whilst hands were flying everywhere to get rid of the autopilot.


Sad but true! Quite how the Captain got away with just a minor bollocking beggars belief! Within this day and age of the MAA I'm guessing that he'd be hung out to dry?


TCF

[NutLoose]

I was there when both episodes happened.

It rather reminds me of the 737 attempting to land in marginal weather at East Midlands.
During the high workload on finals they got a totally inappropriate radio call that resulted in the autopilot being disconnected in error and reconnected as the pilot tried to reply, the resulting crash left the left main gear behind as the aircraft continued on to its final crash landing at Birmingham...

Details

http://aviation-safety.net/database/...?id=20060615-0

[H Peacock]

I seem to recall that most of the damage done to the Tristar was from the second bounce and not the first impact from the "auto land".

Following the first arrival and bounce, the crew applied a large helping of nose-down. The Direct Lift Control (DLC - very clever in its day) correctly interpreted this as a need to increase the RoD whilst also trying to hold the attitude, and deployed most of the spoilers - inevitably resulting in a much harder arrival than the first!

[Juan Tugoh]

I seem to recall that most of the damage done to the Tristar was from the second bounce and not the first impact from the "auto land".

Indeed it was a failure to understand the automation, which lead to the initial impact. The failure to correctly hand fly the recovery, as a result of a failure to understand the flight control system caused the more serious structural damage.

Not a great day in the office for the guys at the front end.


The TriStar autoland system was fantastic and very capable, indeed many described it as PFM. The weak link in the chain was the aircrew that had inadequate knowledge, training or hand flying skills to meet the challenges they gave themselves that day.

[ShotOne]

RAF TriStars were not certified for Autoland at that point. Rather than a "failure to understand the automation" this was surely a gross and deliberate exceedence of the aircraft capability?

[Juan Tugoh]

The aircraft and it's systems were capable, and a monitored daytime VMC autoland should not have presented a problem to a crew that had been trained and understood the system.

The point you make is valid, as it shows a wllful disregard of the release to service.

[A and C]

I was in BA at the time the Tristar was introduced to the RAF and it was the opinion of some of the BA Tristar experts ( both flight & Ground crew) that some of the RAF policy makers were simply out of their depth and trying to impose an operating system to the Tristar that was far more appropriate to the HP Hastings.

Both the frontline flight & ground crews that the RAF had on the project were generally respected for their abilitys and professionalism but the direction from above was poor, from what I have been told the accident was more a product of systematic failure within the RAF to adapt to the Tristar and draw fully on the expertise avalable within BA.

Unfortunately recognition of the honest mistake and military discipline are not compatible especially when those at the top can find a way of shift in the blame onto some poor unfortunate who has made an honest mistake.

[ShotOne]

You'll have to explain that; are you telling us that the flight crew were unfairly blamed for that accident?

Even if we agree entirely with your first two paragraphs, they knew autoland wasn't certified so that surely takes us out of the realm of "honest mistake". You were in BA; would happen to a BA pilot who committed an identical breach of flying discipline?

[NutLoose]

I thought he departed Brize rather rapidly after that little mishap.

[MightyGem]

Sorry, been off line for a few days.

If they had 'recognised the ident of a beacon' it would have been the same anyway.

Correct, which is why, in theory, they should have checked the Lat and Long. The nav chart identified the ROZO beacon with an "R". The PNF entered "R" expecting that it would show the ROZO beacon as the nearest one; ie, at the top of the list. He automatically excepted the one at the top of the list, but it was the ROMEO beacon. The ROZO beacon was list as ROZO and didn't show up with just the "R", but the crew weren't aware of this.

[TheChitterneFlyer]

[quote]I thought he departed Brize rather rapidly after that little mishap.[unquote]


He probably did, though, I cannot now remember. I did hear, on the recent grapevine, that he's now a departed soul.