PPRuNe Forums - View Single Post - High accident rates in light twins an alternative?
Old 28th May 2008, 14:48
  #6 (permalink)  
Pace
 
Join Date: Jan 2001
Location: In the boot of my car!
Posts: 5,982
Likes: 0
Received 0 Likes on 0 Posts
>If you aren't climbing at blue line speed, i.e you are only just maintaining altitude, then you are using all the available power. If you don't have excess power to climb, you also don't have excess power to accelerate. If you DO have excess power to accelerate, you are always going to ALSO have excess power to climb.

What you seem to be getting at is keeping some extra margin over blue-line to alow for gusts etc. Fine- but holding a constant speed just above blue-line is going to be more efficient and give you a better net flight path than the "saw tooth" flight path you seem to advocate.

Unfortunatley there are no free lunches in physics- either the power is there or it isn't!<

Wizofox

But it is Physics and there are no free lunches as you put it but the wrong way. With one engine out in a climb you have drag that you do not need to have. You have extra drag from a higher angle of attack on the wings and the slower you are the more rudder you will require to combat the yaw.
Its all a vicious circle.
By reducing the pitch you are reducing the drag and hence the aircraft will make the most of the available power and accelerate as it accelerates less rudder sticks out in the airstream.

On a hot day at Grosse weight your other engine might be there to carry you to the crash site. Before you make a forced landing this trick might work. As I Said go try it as its another option up your sleeve before taking to the trees.
And yes it is all about Physics so please do feel free to pull the Physics apart because it is for discussion.

Also remember we are always playing with available power and drag but we always have another source of extra power, an extra engine if you like and that is the kinetic energy inherant in the aircraft by using pitch or your
control column.

In a single engine aircraft with the engine out you have only that spare engine (kinetic energy) to maintain your speed to a forced landing. Instead of your throttle controlling your power. Your control column becomes your throttle and you are trading altitude to get that energy

Pace

Last edited by Pace; 28th May 2008 at 15:17.
Pace is offline