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Old 13th July 2010 | 23:15
  #27 (permalink)  
rsiano
 
Joined: Jan 2008
Posts: 61
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From: Doylestown, Pennsylvania
A critical look at reduced thrust takeoffs

A critical look at use of reduced thrust takeoffs. Why ever use it?

I have been critical of the use of reduced thrust for takeoffs for more than forty years. The arguments made in favor of using it to save money and engine life were never good enough for me. Especially when you took a good look at the negative side of using it.

When reduced thrust is used for takeoffs the amount of runway required to accelerate to V1 is increased substantially. This leaves you with less runway remaining in the event of encountering a high speed aborted takeoff.

If you do not encounter an aborted takeoff while using reduced thrust, you are still going to pay the piper by extending the time you and your aircraft spend below 1,000 feet above the ground. I believe the time we spend at less than a thousand feet above the ground is more likely to expose us to a greater chance of an accident.

This will happen as a result of the lower rate of climb due to the use of reduced thrust. Maximum thrust will allow you to spend less time below 1,000 feet above the ground and therefore in my opinion, will enhance the over all safety of the flight.

Reduced thrust takeoff power settings were not mandated but instead were to be used subject the captains discretion. He was not permitted to use the reduced power if the runway was not clean and dry or if a tailwind existed or if he suspected wind shear in the takeoff area.

I used to ask my co-pilots how could you not suspect wind shear on takeoff? Is there some magic combination of wind velocity, direction and temperature or other atmospheric aspect that could deliver that information to the pilot? I know of none.

Therefore, I feel the use of reduced thrust takeoffs should never be used on any takeoff. Yet even when I would explain my reasons stated above to other pilots, many would go ahead and use it over and over again.

I guess I was not a very effective communicator. Maybe one of you could offer a plausible explanation why pilots continue to use reduced thrust takeoffs very day. The last time I used it was in 1967 and although I had many company as well as FAA check pilots fly with me through the years, none ever wrote me up for not using it.

What do you think?
Thanks!
Dick
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