CMA Incident in Rainbow Lake

[iflyforpie]

P.S. I can also find lots of accident reports of pilots rejecting after V1 and putting it in the weeds, often with fatalities, where the aircraft was perfectly capable of flight.

Here's a Canadian classic...


http://www.tsb.gc.ca/ENG/rapports-repor ... 5h0015.asp

Not only was the rejection uncalled for, but the calculated V1 didn't even apply due to a rolling takeoff and takeoff thrust being set well into the roll. That one could have been pretty nasty...

[Go Guns]

Balanced Field Length is not necessarily the same as TOFL. Balanced Field uses a sliding V1 in order to equalize accelerate stop/go distances. In the end it is the same result, you get a limiting number for takeoff, except that BFL will give a more optimized (shorter) distance.

I'll agree with all that, but the argument is pretty much moot. The only numbers you have for the B350 and the 1900D are TOFL, so they're the only numbers you're allowed to use. Now, with that in mind, a bunch of posts back you said that no King Air series uses a balanced field. All I was trying to say is that the King Air 350 does.

I appreciate what you're getting at with your posts. Not everything is as black and white as some would like to have it. A little common sense does go a long way.

[BTD]

P.S. I can also find lots of accident reports of pilots rejecting after V1 and putting it in the weeds, often with fatalities, where the aircraft was perfectly capable of flight.

Here's a Canadian classic...


http://www.tsb.gc.ca/ENG/rapports-repor ... 5h0015.asp

Not only was the rejection uncalled for, but the calculated V1 didn't even apply due to a rolling takeoff and takeoff thrust being set well into the roll. That one could have been pretty nasty...

This was actually the report I was thinking about when I mentioned the L1011. I guess it was a DC-10.

While the report shows the reject to obviously be an incorrect decision, here is an interesting quote from the report.

The captain's decision to reject was based on the fact that he did not recognize the initial sound and subsequent thumping noises, and that, because he thought the bang could have been a bomb, he had concerns about the integrity of the aircraft and its ability to fly. Also, the captain stated that, based on the rejected take-off provisions in the DC-10 Flight Manual and on a fatal DC8 accident that he had witnessed, he had developed a mental rule to not take an aircraft into the air if he suspected that there was aircraft structural failure.

The captain indicated that the time delay between retarding the power levers and selecting reverse thrust was, in part, due to an expletive expressed by another crew member, which interrupted his thought process.

The FDR data showed that, when the captain made his decision to reject the take-off, the number 1 engine EGT was above 950 degrees and the N1 speed had decayed to below 85 per cent. None of the crew members noticed anything unusual about the engine operation during the take-off roll, including the second officer, whose prime duty is to watch the engine instruments. The crew reported being extremely startled by the suddenness and intensity of the loud bang, and none of the crew members recognized the sound or its origin. Because the number 1 engine was still operating in the idle range when the aircraft came to a stop, the crew were not aware that there had been a power loss on that engine until this fact was discovered on the FDR data.

The captain's understanding was that an engine failure would not be an adequate reason to initiate a rejected take-off after V1. In this case, however, prior to making his reject decision, he did not see or perceive indications, or hear advice from his crew, that an engine failure had occurred. Also, the loud bang was neither similar to any compressor stall symptom that he knew about, nor similar to sounds that he had heard in training or experienced during actual flying.

All the members of the flight crew reported that the sound was unlike anything they had heard before. Not only was the bang very loud, but it was difficult to specify its point of origin. None of the crew saw the engine fail light illuminate<23>, nor did they notice the drop in N1. The only cue the captain received to indicate that the take-off was no longer normal was the loud bang, followed by a series of thuds and vibrations. Because the situation did not match any of the captain's previous training or actual flying experience, he was required to respond instantly to the situation by drawing on whatever knowledge or other experience he had.

When the captain heard the loud bang, he immediately thought of a bomb. The only procedural guidance available for this circumstance was that a rejected take-off after V1 could be initiated when "the captain believes that the aircraft has suffered catastrophic failure and will not fly." According to the captain, his action was probably also influenced by the fatal DC8 occurrence that he had witnessed and which resulted in his mental rule of thumb that if structural failure were suspected, he would not take the aircraft into the air.

Interesting report to study. In all honesty if it were a bomb as the captain believes. It may be better to end up off the end at 40 kts with a damaged airplane then a smoking hole in the ground because half your aircraft was gone.

Here's a photo of an airplane where the crew made the correct decision to continue the take-off. Unknown to them, the departing engine took a whole bunch of sh*t with it. V1 relates to engine failures only, nothing else, and no matter how much you want it to be, its not always black and white.