Warning: Your Takeoff rotation may be an accelerated stall manuver

[UALRATT]

Boeing publishes a recommended all-engine normal takeoff procedure in the Flight Crew Training Manual (FCTM) for 727, 737 Classic, and Next-Generation 737, 747, 757, 767 and 777 models and in the Flight Crew Operations Manual for 717, MD, and DC models. In order to avoid tire-speed-limit exceedance during takeoff, Boeing stresses adhering to the recom­mended average all-engine takeoff rotation rate of 2 to 3 degrees per second, which provides adequate tail clearance margins with a target liftoff attitude reached after approximately 3 to 4 seconds


I agree. Read what it says! 2 to 3 degrees per second. Some of these guys on the 80's are reaching 20 degree's pich in 3 to 5 seconds. It should be taking them 7 to 10 seconds to reach that pich attitude.

Something else that I don't think people are figuring is that you are definately above your computed takeoff weight on most takeoffs. Standard winter and summer weight plus checked baggage weights are probably much lower than your actual weights for each. This means that your takeoff speeds are more than likely too low. Another reason why you don't want to jerk the thing off the ground!

I have never flown an MD series aircraft but according to the data the recommendation for this type of aircraft is 5-7 seconds to a max of 20 degrees. Good suggestion is to forward them (Boeing) for evaluation your thoughts about 7 to 10 seconds. Much easier to explain to the hearing board if one were to survive a mishap...

 

[Abernathy]

I'm glad this thread came up because I've seen some pretty atrocious rotations. I flew with a CA this past summer who used to rotate so quickly I nearly jumped out of my seat. It continued through the 4 day trip and I made a comment about it, being careful not to call his rotation habit out explicitly, and he went off on a rant about pilots who rotate slowly and how you need to get the plane off the ground, and "not to worry" because the plane will not tailstrike.

That told me two things:

1. He thought that this was not only an acceptable rate of rotation, but also the PROPER technique. (I'm talking rotation at a rate that I have never seen before, neither before flying with him nor in the several months after).

2. "Don't worry it won't tailstrike" told me that he doesn't seem to understand what the real problem is with quick rotation. I wasn't worried about a tailstrike. I don't want an accelerated stall 3 feet off the ground.

The strange part is how stubbornly he seemed to believe in his technique. I've never seen such an odd technique so stubbornly defended.

 

[Quimby]

I'm glad this thread came up because I've seen some pretty atrocious rotations. I flew with a CA this past summer who used to rotate so quickly I nearly jumped out of my seat. It continued through the 4 day trip and I made a comment about it, being careful not to call his rotation habit out explicitly, and he went off on a rant about pilots who rotate slowly and how you need to get the plane off the ground, and "not to worry" because the plane will not tailstrike.

That told me two things:

1. He thought that this was not only an acceptable rate of rotation, but also the PROPER technique. (I'm talking rotation at a rate that I have never seen before, neither before flying with him nor in the several months after).

2. "Don't worry it won't tailstrike" told me that he doesn't seem to understand what the real problem is with quick rotation. I wasn't worried about a tailstrike. I don't want an accelerated stall 3 feet off the ground.

The strange part is how stubbornly he seemed to believe in his technique. I've never seen such an odd technique so stubbornly defended.

Ignorance is bliss.

 

[JT12345]

If you get a yanker that is stubborn...

don't call Vr until Vr+10

I had a guy that wouldn't listen to me either. What else can you do? Maybe Pro standards?

 

[Tail Gunner Joe]

It took the DC 10 crash at ORD to show what slowing to V2+10 can do under special situations.

You lost me here:
What did an engine separating from a DC-10 teach us about 'V2+10'?

 

[LJ45]

You lost me here:
What did an engine separating from a DC-10 teach us about 'V2+10'?

They lost slats on one side because of a hyd break and when they slowed they stalled that wing and rolled over. If they would have maintained their climb speed, instead of slowing, they wouldn't have stalled.

 

[whymeworry?]

This drives me nuts. I see it all the time. I finally started just putting a finger or two up to prevent the other guy from over-rotating. Got sick of wasting my breath teaching them the 2-3 deg/ sec technique. The airplane I fly is quite prone to tail strike. So in addition to the stall issues/ Eng loss during rotation, there is the tail scrape to worry about; which IMO should never occur on TO (yet it seems to happen pretty often enough if you look at global accident/ incident reports).

Just happened 3 weeks ago on a TG 747-400... not even a tail strike prone plane.

http://www.ntsb.gov/ntsb/brief.asp?ev_id=20100305X54655&key=1

 

[Tristar]

Yet a few pilots rotate at 7 degrees per second. They tell me they want to maintain V2 to V2+10. This speed is a minimum at 35 feet above the ground not a maximum during climbout.

First off, I agree with your premise.

I think part of this may come from many noise abatement profiles (at least where I often fly) call for maintaining V2+10 to acceleration altitude. I'm guessing some people lose (not loose) sight of the forest for the trees - the primary task is getting the aircraft airborne at the appropriate pitch attitudes (and in turn airspeed) to insure the required performance is met (including not hitting the tail, not running into the dirt, not hitting close in obstacles, having adequate stall margins, etc.). Noise abatement comes AFTER all of that.

I've ridden in the back with a few of these clowns, it really concerns me because one of these days one of them is going to create an incident or accident. They are either going to hit a tail (try that aggressive rotation in a heavy 757-300, IIRC tail clearance is only about 3 feet when done properly) or do Vmc demo if they lose an engine right around rotation. There is no reason for it, it's just another example of very poor airmanship.

PS - CaptSeth: You are correct - I never saw this problem at at our previous carrier, or even where I am now. I do see it from time to time riding in the back, at both regionals and majors. I really wonder where some of these guys learned to fly.