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View Full Version : "Positive rate - gear up" Oops too late


sheppey
1st Jul 2017, 08:42
On 30 September 2015, a Bombardier DHC-8 400 being operated by an airline based in Luxemburg and holding a Luxemburg AOC on a scheduled passenger flight from Hamburg to Luxemburg via Saarbrucken failed to get airborne in normal day visibility at the end of its take-off roll when the landing gear unexpectedly retracted. It then slid almost to the end of the runway before stopping. There was no fire but an immediate passenger emergency evacuation was initiated by the cabin crew because of "smoke and an acrid metallic smell" which had developed during the slide along the runway. None of the 20 occupants were injured but the aircraft sustained severe damage

Read more: https://www.skybrary.aero/index.php/DH8D,_Saarbrucken_Germany,_2015?utm_source=SKYbrary&utm_campaign=2fd25523ca-524_Landinggear_V1_12_06_2017&utm_medium=email&utm_term=0_e405169b04-2fd25523ca-276530305

Seems the first officer inadvertently selected wheels up too early. During simulator training in Australia, it is not uncommon to see the PM reach across and place his hand on the undercarriage lever at VR in anticipation of the PF calling gear up. On a similar vein, when the captain's static vent is blocked during the take off roll as part of the erroneous airspeed exercise in the 737 simulator, the first indication after lift off is that the captains altimeter and VSI does not move due to the blocked static vent. On the other side of the cockpit, the first officer's altimeter and VSI work normally. The F/O sees his instruments displaying a positive rate of climb and calls "positive rate" Invariably the PF replies "Gear Up" when in fact he does not have an indication that his altimeter and VSI are going up. In other words the PF hears the call of "Positive rate of Climb" and without hesitation answers with "gear UP' because that is always what he has done.

The incident described in the report describes succinctly the danger of early anticipation. Good time to sit on your hands?

Tankengine
1st Jul 2017, 09:23
On 30 September 2015, a Bombardier DHC-8 400 being operated by an airline based in Luxemburg and holding a Luxemburg AOC on a scheduled passenger flight from Hamburg to Luxemburg via Saarbrucken failed to get airborne in normal day visibility at the end of its take-off roll when the landing gear unexpectedly retracted. It then slid almost to the end of the runway before stopping. There was no fire but an immediate passenger emergency evacuation was initiated by the cabin crew because of "smoke and an acrid metallic smell" which had developed during the slide along the runway. None of the 20 occupants were injured but the aircraft sustained severe damage

Read more: https://www.skybrary.aero/index.php/DH8D,_Saarbrucken_Germany,_2015?utm_source=SKYbrary&utm_campaign=2fd25523ca-524_Landinggear_V1_12_06_2017&utm_medium=email&utm_term=0_e405169b04-2fd25523ca-276530305

Seems the first officer inadvertently selected wheels up too early. During simulator training in Australia, it is not uncommon to see the PM reach across and place his hand on the undercarriage lever at VR in anticipation of the PF calling gear up. On a similar vein, when the captain's static vent is blocked during the take off roll as part of the erroneous airspeed exercise in the 737 simulator, the first indication after lift off is that the captains altimeter and VSI does not move due to the blocked static vent. On the other side of the cockpit, the first officer's altimeter and VSI work normally. The F/O sees his instruments displaying a positive rate of climb and calls "positive rate" Invariably the PF replies "Gear Up" when in fact he does not have an indication that his altimeter and VSI are going up. In other words the PF hears the call of "Positive rate of Climb" and without hesitation answers with "gear UP' because that is always what he has done.

The incident described in the report describes succinctly the danger of early anticipation. Good time to sit on your hands?
"During simulator training in Australia...."
What bloody airline? At mine you would get your hand knocked off, I hope!

dayzel87
1st Jul 2017, 09:48
"During simulator training in Australia...."
What bloody airline? At mine you would get your hand knocked off, I hope!

Same here, I'd like to think it would be extremely unlikely you would get away with that at my airline either.

Shagpile
1st Jul 2017, 11:00
Same here, I'd like to think it would be extremely unlikely you would get away with that at my airline either.

I found a lot of my time instructing ab-initio students was teaching them how & when to put their hands and when/where to look. It takes a little bit of time to get comfortable, but eventually you look at the student a lot and can pick up most root causes of why they are doing something wrong.

When I was teaching instructors, I'd get them to look at me a lot when trying to discover the root cause of errors. In the sim, these kinds of copilot shenanigans should be caught by the instructor looking at the person being checked.

You can pick up all kinds of things like making sure they transition to instruments very early during an instrument/night takeoff instead of rotating visually and waiting till they are lost before looking down.

Judd
1st Jul 2017, 14:39
hands?"During simulator training in Australia...."
What bloody airline? At mine you would get your hand knocked off, I hope! Same here, I'd like to think it would be extremely unlikely you would get away with that at my airline either.
Agreed. Piss poor practices like that are just an accident waiting to happen.



Lighten up chaps.:ok: You are missing the whole point made by the OP. All sorts of strange and frightening scenarios happen during simulator training all over the world. These things happen and don't necessarily reflect what happens on line. Simulators are there for just that - training. By the very nature of the job, check pilots in simulators witness many more "events" than the average Joe Pilot who gets only two sim sessions a year.

Tankengine
1st Jul 2017, 22:34
Lighten up chaps.:ok: You are missing the whole point made by the OP. All sorts of strange and frightening scenarios happen during simulator training all over the world. These things happen and don't necessarily reflect what happens on line. Simulators are there for just that - training. By the very nature of the job, check pilots in simulators witness many more "events" than the average Joe Pilot who gets only two sim sessions a year.
Judd, I think that a Dash strewn along the runway proves that bad training in a simulator can lead to accidents online!

Duck Pilot
1st Jul 2017, 23:47
Not sure what the experience of the pilot was who pulled the gear up, however I've seen similar potential actions by junior pilots reacting to scans/situations and checklists without considering the current state of the aircraft. Operating like a robots, good training should stamp theses bad habits out.

Going Nowhere
2nd Jul 2017, 00:15
3295 total time with 1483 on type.

Di_Vosh
2nd Jul 2017, 13:05
TBH, sheppey, I'm not certain that this particular incident is a great example of "early anticipation".

One of the reports I read on this incident mentioned that the investigation looked at 30 random take-offs as well as the previous 29 take-offs where the FO was PM, and none of them showed any evidence of early gear retraction.

The investigation concluded that she had a "slip" (i.e brain fart).

DIVOSH!

CaptainInsaneO
3rd Jul 2017, 10:04
Hi DiVosh,

PNF (PM) wasn't all to blame for that one...mostly yes, but look at what the PF says during the takeoff sequence:

10:16:24 PF take off, my controls
10:16:25 PNF your controls
10:16:27 PNF spoiler is closed
10:16:30 PNF autofeather armed
10:16:33 PF looks like spring
10:16:35 PNF yeah, power is checked
10:16:36 PNF 80 knots
10:16:37 PF checked
10:16:40 PNF V1, rotate
10:16:42 Background click sound, probably gear lever UP
10:16:43 PNF upps, sorry

"Looks like spring"...!
Random chatter/comments during that phase or radio calls directed to you with no relevant information can be very distracting (evidently with this accident) and highly unprofessional. Distracting enough to even cause some people to 'fart'.

If the investigation went back over so many flights to check to see if the PNF was doing early retracts, I think it would've been a good idea to see if the PF was making random, distracting comments through such a critical phase of flight as well. (I understand CVR's rewriting themselves would make this hard)

Good idea to read the 'GEAR UP' next to the lever (to yourself) before using it.

Centaurus
3rd Jul 2017, 13:31
Reminds me of this apocryphal story:
TRUE PILOT STORY
"The C-119 (flying boxcar) flown in the Korean Conflict had more than one problem. A serious one was its tendency to reach takeoff speed then lose some power. If you were not aware of this and attempted to take off at proper speed instead of waiting another couple of seconds for proper power you could have a problem. This morning the newly-assigned co-pilot was paired with a hard-nosed Major as captain. The co-pilot was nervous and it showed in his actions. As they approached and gained take off speed, the Major decided to soften his image as difficult and turned to the new co-pilot and quipped 'cheer up.' The co-pilot executed the 'gear up' maneuver just as the power drop occurred. The plane came back to the runway without landing gear. No one was injured. No blame was placed for the incident."

noflynomore
3rd Jul 2017, 13:48
Yet more confirmation, as if any were needed, of the hazardous nature of the call "Positive rate" - which is a VSI function.
It is surely far safer and more prudent to change the mindset a little and use "Positive climb", an altineter based call that eliminates a false call ffrom either a bounce or poorly damped VSI and predicates the gear up only once the slower reacting altimeter has started to register a change of altitude.

Captain Dart
3rd Jul 2017, 23:31
My lot use 'positive climb', I think it is now a general Airbus thing. If you're lucky enough to have a RADALT, that's a good crosscheck.

Bravohotel
4th Jul 2017, 00:30
Centaurus
regarding the C-119 incident many years ago a friend was doing his glider tow rating in a Piper Cub with the instructor seated in the back seat during the climb out around 200ft the instructor yelled out (no intercom) "Relax" he thought she said "Release" so he pulled the tow release the experienced glider pilot was able to complete a successful return to land with the tow line still attached to his glider.

Di_Vosh
4th Jul 2017, 10:56
CaptainInsaneO


Agree mate, and I saw that as well. I just don't think that this incident was a 'good example' of 'anticipation', that's all.

I'm also not that convinced that the distraction introduced by the Captain should have been enough to cause the incident in question.

The thing is, is that there are plenty of distractions that can happen during the take-off roll (radio calls to other aircraft, birds, wind-gusts, etc). If these were genuine distractions I think we would be seeing more take-off incidents.

In any case, lessons to be learned from this incident.

At our airline, we require two indications (e.g. IVSI and radalt) before calling 'Positive Rate'.

DIVOSH!