5/18/2013

Takeoff Safety


Takeoff  Safety




The Goal of this post aid is to focus all Pilots to read and review this material. I want to share with the Aviation Community all around the world this interesting understanding guide to Takeoff Safety and reduced the number of RTO related accidents by improving the pilot’s decision making and associated procedural accomplishment through increased knowledge and awareness of the factors affecting the successful outcome of the Go /No Go decision.

 Perhaps you as a Pilot never have had the experience to reject a takeoff in the real life, but anyway of course this is a normal procedure you practice on your simulator training, but the day that you have to, you need to be understand and be prepared regarding several lessons can be learned from these RTO accidents in the past. First the Crew must always be prepared to make the Go / No Go decision prior to the airplane reaching V1 speed.

A good brief statement of these lessons is, as speed approaches V1, the successful completion of an RTO becomes increasingly more difficult.




The Takeoff Rules

It is important that all pilots understand the takeoff filed length / weight limit rules and the margins these rules provide. Misunderstanding the rules and their application to the operational situation could contribute to an incorrect Go/ No Go decision and could be ended in an incident or accident.

Decisions and Procedures / What Every Pilot Should Know

There are many things that may eventually affect the outcome of a Go / No Go decision. The Goal of the Takeoff Safety Training Aid is to reduce the number of RTO related accidents and incidents by improving the pilots decision making and associated procedure accomplishment through increased knowledge and awareness of the related factors.




V1 Sped Defined

What is the proper operational meaning of the Key parameter V1 Speed with regard of the Go / No Go decision criteria? This is not such an easy question since the term V1 Speed has been redefined several times since commercial jet operations began more than 30 years ago and there is possible ambiguity in the interpretation of the words used to define V1.

The FAA regulations on paragraph 25.107 defines the relationship of the takeoff speeds published in the Airplane Flight Manual, to various speeds determined in the certification testing of the airplane.
The most important statement within this official definition is that V1 is determined from … the pilot’s initiation of the first action to stop the airplane during the accelerated –stop tests.  

One common and misleading way to think of V1 is to say V1 is the decision speed. This is misleading because V1 is not the point to begin making the operational Go / No Go decision. The decision must have been made by the time the airplane reaches V1 or the pilot will not have initiated the RTO procedure at V1, therefore by definition, the airplane will be traveling at a speed higher than V1 when stooping action is initiated, and if the airplane is at a Field Length Limit Weight, an overrun is virtually assured.

Another commonly held misconception V1 is the engine failure recognition speed, suggests that the decision to reject the takeoff following engine failure recognition may begin as late as V1, again, the airplane will have accelerated to a speed higher than V1 before stopping action is initiated.

The certified Accelerated – Stop Distance calculation is based on an engine failure at least one second prior to V1. This standard time allowance has been established to allow the line pilot to recognize an engine failure and begin the subsequent sequence of stopping actions.

In an operational Field Length Limited context, the correct definition of V1 consists of two separate concepts:

First with the respect to the No Go criteria, V1 is the maximum speed at which the rejected takeoff maneuver can be initiated and the airplane stopped within the remaining field length under the conditions and procedures defined in the FARs. Is it the latest point in the takeoff roll where a stop can be initiated?

Second with respect to the Go criteria, V1 is also the earliest point from which an engine out takeoff can be continued and the airplane accomplishes a height of 35 feet at the end of the runway.

The Go / No Go decision must be made before reaching V1 A No Go decision after passing V1 will not leave sufficient runway remaining to stop if the takeoff weight is equal to the Field Length Limit Weight .

When the airplane actual weight is less than the Field Length Limit Weight, it is possible to calculate the actual maximum speed from which the takeoff could be successfully rejected. However, few operators use such takeoff data presentations.

It is therefore recommended that pilots consider V1 to be a limit speed. Do not attempt an RTO once the airplane has passed V1 unless the pilot has reason to conclude the airplane is unsafe or unable to fly. This recommendation should no matter what runway length appears to remain after V1.

Most of the information gathering related on this support to all pilots regarding this Takeoff Safety subject, it is very important to understand that all crew members on the flight deck play an important role in the Go / No Go decision and RTO maneuver. Company policies shape these roles. However, how team is organized for each takeoff can make a difference in team performance.

Knowing your own capabilities and that of the other crewmembers is part of Situational Awareness and should be used in planning for a given takeoff.
Always consider the possibility of an RTO when assigning takeoff duties.  

CRM is very significant and each airline approaches the use of a good Crew Resource Management in a slightly different manner, but the goal of effective teamwork remains the same.
CRM is good example information that could be used to promote a common perception of RTO problems and actions.


Tradewinds Boeing 747 Rejected Takeoff Crash. Click on the link

Stay Safe, Someone at Home is waiting for you. Always Fly Safely

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