Boomer

Since we're thinking "out of the box"...

What's the proper action if, after V1 but prior to Vr, the aircraft suffers a malfunction that causes it to slow back down below V1? Then can you "legally" abort?

Blkflyer

As Stated earlier the time between V1 and Vr is so small you are most likely going.. as one of my riddle professors use to say Measure with a Micrometer and cut it with an AX


Fly safe yall

Slice

Well if you're below rotation speed it probably won't fly. But the point in space is still behind you(original V1 point). So the 2nd V1 indication really has no meaning. However, I'm not worried about legal if there's an uncommanded deceleration on my takeoff roll.

Blkflyer

You are right I think I was given a stagnating airspeed on TO roll in the sim out of LGA before we knew it we were dang near in the Drink I think the point the instructor was trying to make was we could have started the rotation but at a much slower rate than normal.. talk about pucker factor

shackone

Most of the posts here have been examples of anything but 'thinking outside the box'...in fact, they have been nothing but parroting of rote procedure.

A Captain's emergency authority is there for situations like this one...where circumstances that might be considered written in stone may not be. Depending on what those circumstances are, I see no problem with a rejected takeoff at V1.

All things considered, E1Out's post reflects the best grasp of real world reality.

JetJock16

Funny, I though we we're talking about after V1.

Either way, if you have a problem with pilots thinking outside the box then don't fly with the Chinese.

Slice

Are we really going to split RCH's on this one?
There are always exception but in general, I'm most likely going to play the percentages and take her into the air. I usually need the landings anyway.

SaltyDog

I agree with Subicpilot

If I have a Valuejet fire, now I know about it, (they didn't) but I still cannot fight the fire. Thinking about how close the DC-8 came to crashing in PHL last year with a cargo fire. My ops thinking is like my Navy training. I would evaluate the runway environment, flat, smooth over run?, Good CFR folks on station? Wx.. is it VFR and I can immediately turn downwind? or will I have to go out and set up for a possible lost com ILS etc? No same answer depending on environment and crew capability (yes, our reputations precede us <g>) But if I get a cargo fire, I would rather do the Tradewinds off runway excursion and jump out than crash like Valuejet turning around.
In any case, under normal training RTO procedures, one should think seriously about conducting high speed RTO's (above 80-100 kias) because they get dangerous the higher the energy state. In my case, if I blow a few tires at 100 kts, I am going flying, not doing an RTO that likely takes me off the RY anyway. This is all great layover/training center discussion BTW. For the original poster, I would have taken it airborne <g>

The industry came up with the Takeoff Safety Training Aid in the early 90's. Here is what Boeing put out about it.
"Takeoff safety
A flight crew may reject a takeoff for a variety of reasons, including engine failure, direction from air traffic control, blown tires, or system warnings. A takeoff under these conditions may result in a diversion or delay, but landings are usually uneventful. In about 55 percent of rejected takeoffs (RTOs) the airplane would have had an uneventful landing if the takeoff had gone ahead.

While most RTOs are without incident, they do account for a significant number of accidents, as well as damage to the airplane. Following are some statistics about RTO accidents and incidents:


More than half the RTO accidents and incidents reported in the past 30 years were initiated from a speed in excess of the maximum "go/no go" speed before the airplane must take off.

Approximately one-third reportedly occurred on runways that were wet or contaminated with snow or ice.

A little over one-fourth of RTO accidents and incidents were caused by loss of engine thrust.

Almost one-fourth of RTO accidents and incidents were the result of wheel or tire failures.

Approximately 80 percent of RTO overrun events could have been prevented by appropriate operational practices.
An RTO occurs approximately once in every 3,000 takeoffs. However, many RTOs may not be reported; the actual number may be estimated at one in 2,000 takeoffs. While RTO overrun accidents and incidents persist, the rate of occurrence continues to drop. Compared to the 1960s, the 1990s showed a 78 percent decrease in the rate of RTO overrun accidents and incidents.

In 1992, with the endorsement of the FAA, Boeing, along with members of the aviation industry, published the Takeoff Safety Training Aid. The aim of this training aid is to reduce the number of overrun accidents and incidents resulting from high-speed rejected takeoffs. Boeing and members of the aviation industry also formed an international takeoff safety task force that recommended developing training practices and operational guidelines and improving how the full-flight simulator is used.

Engine, tire and brake suppliers are also working to improve their products. The airlines are continuing to develop effective training in the areas of takeoff decision-making and how to handle rejected takeoffs."

The concepts are covered in Advisory Circular 120-62 found here: http://rgl.faa.gov/Regulatory_and_Gu...0!OpenDocument

shackone

The original post said it this way..."We received the engine fire notification the second we hit v1".

The type of aircraft, length of runway, and exact point of the emergency all justify the POV that this is not a black and white question.

Any Captain that taxis out onto the runway with the idea that an engine failure is a canned situation is in the wrong seat.

III Corps

V1 is a decision speed. Simple.

If, as others have noted, you have a 5 mile long runway, you can brief, "We don't have a V1 speed so if anything happens prior to liftoff, we will abort."

BUT if you are going to computer a V1 speed, if expectations are that anything prior, you abort and anything after, you go... you do as briefed.

At or near V1 you are accelerating at about 7-10kts per second. Not a time to begin discussions on whether to go or to abort. There are more than a few airframes that got bent because guys were sure they had enough runway.