# Power changes and speed

#### SGK

##### Member
This may sound as a non-question, but when writing official documets, it's important to be clear, especially when teaching the students.

The document "PPLG-Syllabus-2009-Rev-A" by British Rotorcraft Association on page 19 specify "Full power climb into a low power descent":
"From straight and level flight climb on full power to a given altitude at least 300ft above the starting altitude maintaining a constant speed and direction and maintaining balance at all times. As soon as the given height is reached, immediately descend on idle power levelling out at the original altitude."

as well as similar manouver "Figures of 8 climbing, then descending, then climbing. Constant speed" on page 46 which says:
"Perform figures of 8 at a constant speed and height around 2 points approx 100metres apart. Initiate a full power climb to a given altitude at least 400ft above the starting altitude whilst maintaining the figure of 8 pattern. At the end of the climb immediately initiate a low power descent whilst maintaining the figure of 8 pattern. At the end of the figure of 8 pattern immediately initiate a full power climb and repeat the exercise."

while the "Flight Manua MTO Sport", Section 10, SAFETY TIPS" in section about "Low-G Avoidance" tells following:
"Never push the control stick forward to descend or to terminate a pull-up (as you would in an airplane). This may produce a low-G (near weightless) condition which can result in a situation with reduced or lost lateral roll control and significant loss of main rotor RPM. Always reduce power to initiate a descent."

Power reduction during full power climb immediatelly reduces the speed, and it takes time to catch the speed again by lowering the nose in a safe manner.

Question: Do you think that lowering the nose followed by power reduction in order to maintain the speed during training should be a forbidden manouver? If yes, why the syllabus insists on maintaining the constant speed?

It’s a rotorcraft not an airplane. Reduce power than lower the nose. Unlike what is done in airplanes where you lower the nose trim speed and then reduce power. That will create low G. That is not good in rotorcraft. It’s a subtle but important difference and one which gets airplane pilots who fly less by feel get in trouble because they have no sense that G load is being reduced. I am amazed by the lack of feel many airplane pilots demonstrate. Not all but definitely more significant number than one would imagine. The guys who fly jets are the worst.

Last edited:
I would assume that maintaining constant speed is to reinforce the idea that power controls climb while pitch controls airspeed, which many students get wrong. Full power climbing and idle descending all at the same speed will demonstrate to to the student that power is not a speed control; you can run through the whole power range without variation in speed.

When I started flying airplanes, I was taught at the very beginning, power / throttle for climbs and descents. pitch and trim for airspeed. This methodology creates stabilized climbs and descents. Unfortunately, the past several generations of airplane pilots have not been taught this in the beginning. So they are chasing their airspeeds and attitude all over the sky.

Learning to fly gilders first taught me what my feet are for. To correct against adverse yaw by leading with rudder when starting a turn and to keep the aircraft and turn coordinated. I learned to feel slips and skids with my posterior. I learned to detect subtle changes in airspeed by listening to the wind passing over the airframe with my ears. The smells of cut grass, a restaurant cooking food, a manure pile fermenting let me know that warm air is rising very well. I learned to use my senses for flight. All valuable skills that transferred to power flight. The first time I flew a helicopter with a high time Army combat veteran, Robert Maxwell (the creator of the Maxwell Rocket System for the UH-1 in Vietnam), he said, “You’re a glider pilot. You lead your turns with 'rudder' ” and "(I'm) definitely a seat of the pants flyer."

So adding or reducing power before moving the cyclic to control airspeed in a gyroplane is not a foreign concept to me.

Unfortunately as you mentioned Abid, the skill sets that I have mentioned in the above paragraph are no longer taught to new pilots. They fly with feet flat on the floor and cannot comprehend using their senses to maintain smooth and coordinated flight.

Wayne

Replies
40
Views
2K
Replies
100
Views
9K
Replies
33
Views
3K
Replies
11
Views
2K
Replies
35
Views
3K