# How much could human power add to the endurance of an electric gyrocopter?

If we take a single seater electric gyrocopter like this one, could a human-powered propeller like this add to the endurance of the aircraft? The gyrocopter only needs a 32km/h forward speed to stay airborne.

• Please elaborate on your question. Without clicking the links it is unclear what you are asking. Commented Jun 1, 2016 at 7:31
• Improved wording. Please confirm if better.. Commented Jun 1, 2016 at 12:14
• I think it's pretty clear - I was almost done answering. The electric gyrocopter has a 80kW powerplant, a human is a 300W powerplant - less than 1%. This small gain is completely offset by the extra water your human powerplant needs during exercise. Commented Jun 1, 2016 at 12:15
• I agree with @Federico - I have no idea what I'm supposed to be looking at in the linked jpg. Commented Jun 1, 2016 at 12:25
• My bad. I had the wrong image. Rectified.. Commented Jun 1, 2016 at 12:26

According to the wikipedia page on "Human Power", a trained cyclist can produce about 400 watts of mechanical power for an hour or more, adults of good average fitness can produce between 50-150 watts for an hour of vigorous exercise, and a healthy laborer over the course of 8-hour shift can sustain about 75 watts per hour.

The Electric motor on the autogyro mentioned in the question has an 80kW (i.e. 80,000 Watt) motor. However, as you know most aircraft only use 100% power on takeoff and approximately 75% for fast cruise. For simplicity, I'll assume 75% power for cruise. That is 80kW * 75% = 65kW (i.e. 65,000 Watts). The information from the AutoGyro says the current endurance is 45 minutes.

So, if we assume the "trained cyclist" power output of 400 Watts, which is 0.62% of 65,000 Watts, then it would result in a 0.62% increase to the current endurance of 45 minutes. A 0.62% increase would result in an increased endurance of approximately 17 seconds of flight (45 min * 0.62% = 45.28 min or 45m 17s).

Its important to note that the human powered glider mentioned in the link was designed from the ground up to be powered by human power. It only weighs a fraction of the electric gyro. For example, a similar human powered glider the MIT Daedalus weighed just 69 lbs (31kg)! (https://en.wikipedia.org/wiki/MIT_Daedalus). The gyrocopter in the question appears to be a modified version of the Cavalon model by the company AutoGyro; on it's technical details page it says its empty weight is between 606-672 lbs (275-305kg).

• The Daedalus team used four professional cyclists and assumed only 300 W of continuous power. Commented Jun 25, 2017 at 14:32
• Also... the gyrocopter is not noted for fuel efficiency, as compared to a fixed wing aircraft - lots more drag. Presumably, it would be equally wasteful of human power. Commented Jun 26, 2017 at 2:24

One has to look at the total energy requirement of the gyrocopter. In this instance it is a 80 kW powerplant. A human power plant would be incapable of a sustained output of more than 1kW, therefore I would conclude that the impact of augmented human sourced power would be less than 1% and therefore insignificant.

– Ralph J
Commented Apr 2, 2017 at 20:40
• @RalphJ But it's better for an answer to be posted as an answer than as a comment. Commented Apr 4, 2017 at 1:29
• The truth is, I missed the comment already posted, and my answer was never intended as a restatement of someone's comment. My apologies to Sanchises. I did not comment on the needed forward speed because given the powerplant size, it was unlikely that the drag was below 1 kW. In retrospect, that might have made the answer more complete. Commented Apr 4, 2017 at 15:17
• No need to apologize - barring perhaps using kW/h as a unit ;) Commented Jun 29, 2017 at 8:13
• @Sanchises, ok, fixed. You are right. Commented Oct 3, 2019 at 2:25