Turnback on departure
As a GFI-G having done a lot of instructing in low power motor gliders, motor glider endorsements and evaluating pilots in loss of power on takeoff procedures, I believe the following general considerations apply.
1. At the first hint of loss of power or any idea that the engine is not developing full RPM or other indications lower the nose and establish the recommended glide speed before making a decision about what to do next.
2. When recommended glide speed is established and stabilized assess the situation and determine the executable options. Assume the engine is going to quit and leave you with a high prop drag.
If a 180 is executable establish the bank angle to provide the maximum angular change for minimum loss of altitude. The direction of the turn should generally be up wind if there is any cross wind- results in lower ground speed if you dont make it through the full 180 turn.
Know where the best landing options are on airport other than runways. Generally anywhere on airport is better than anywhere off airport. Better, more accessible for emergency vehicles too.
Some general observation.
Doing these maneauvers at altitude is not the same or even good training for the real thing but is good for developing data that demonstrates the correct speed and bank angle to achieve the maximum heading change for loss of altitude for different aircraft weights. Getting experience at low atitude level flight 180 turns with low power setting flying the correct AOA and bank angle with a suitable experienced instructor is good. Of course if you are using AOA you just need to select the correct AOA and bank angle and airspeed will take care of itself for all weight conditions.
In my experience the biggest mistakes are not getting the nose down and establishing the correct speed before assessing whether a 180 is an option. In a sudden loss of power a significant loss of altitude occurs to recover and stabilize speed. A partial loss of power or a sequential failure sometimes results in delayed recognition and decision making and loss of valuable options. Make the decision early and only invoke executable options. Dont use flaps until you have the final approach and landing in the bag. This whole procedure should be part of the pre take off checklist.
KT
As a GFI-G having done a lot of instructing in low power motor gliders, motor glider endorsements and evaluating pilots in loss of power on takeoff procedures, I believe the following general considerations apply.
1. At the first hint of loss of power or any idea that the engine is not developing full RPM or other indications lower the nose and establish the recommended glide speed before making a decision about what to do next.
2. When recommended glide speed is established and stabilized assess the situation and determine the executable options. Assume the engine is going to quit and leave you with a high prop drag.
If a 180 is executable establish the bank angle to provide the maximum angular change for minimum loss of altitude. The direction of the turn should generally be up wind if there is any cross wind- results in lower ground speed if you dont make it through the full 180 turn.
Know where the best landing options are on airport other than runways. Generally anywhere on airport is better than anywhere off airport. Better, more accessible for emergency vehicles too.
Some general observation.
Doing these maneauvers at altitude is not the same or even good training for the real thing but is good for developing data that demonstrates the correct speed and bank angle to achieve the maximum heading change for loss of altitude for different aircraft weights. Getting experience at low atitude level flight 180 turns with low power setting flying the correct AOA and bank angle with a suitable experienced instructor is good. Of course if you are using AOA you just need to select the correct AOA and bank angle and airspeed will take care of itself for all weight conditions.
In my experience the biggest mistakes are not getting the nose down and establishing the correct speed before assessing whether a 180 is an option. In a sudden loss of power a significant loss of altitude occurs to recover and stabilize speed. A partial loss of power or a sequential failure sometimes results in delayed recognition and decision making and loss of valuable options. Make the decision early and only invoke executable options. Dont use flaps until you have the final approach and landing in the bag. This whole procedure should be part of the pre take off checklist.
KT