Can Wingtip Motors Improve Aircraft Efficiency? RCTestFlight Solar Collaboration Part 1

I really enjoyed this thanks for making it.

I wonder if the vortex interacting with the props make each individual prop get more lift/propulsion. Worded poorly but I think you know what I'm saying. You're forcing more air on each blade.

It would be interesting to see a comparison of wingtip motors in a push vs pull configuration.

Might have been interesting to reverse the rotation direction of the motors and see the implications.

I think in practical GA use, the risks of differential thrust in the case of an engine out, vastly outweigh any efficiency gains.

Check out the development of the Vought V-173. The propellers were arranged to rotate in the opposite direction to the tip vortices, allowing the aircraft to fly with a much smaller wing area, or in your situation should provide greater efficiency

I'm pretty excited about this channel, I hope you continue to grow.

What amazes me is how much work you put into this project. And that your wife comes along to support you. Great photography and narrative.

What a cool concept. I like the way you construct your aircraft too; Looks really professional.

Being an Aircraft mechanic, I'm going to have to doubt a number of statements made at the beginning of the video. Most specifically, I figure that While electric motors are improving all the time, batteries are still nowhere near being able to replace Gasoline or Kerosene (Jet A) as storage mediums for aviation. The simple fact is, for a given energy capacity, batteries still take much more volume and weight to store. The really nice thing about liquid fuels, especially in aviation is the fact that they get used up. By the midpoint of a flight, on even say a Cessna 172M, the airplane can be as much as 130lbs (approximately) lighter (22 gallons out of a maximum of 46). Batteries leave you dealing with a not insignificant chunk of dead weight once the battery is depleted. This is before you even start considering the impact of potential surprise condition changes during a given flight. When running on battery, your maximum range is directly dependent on the other uses of electricity, and if say you wind up finding a IFR condition by nasty surprise (it happens more than you think), suddenly your range figures could go down below the minimum safes. Liquid fueled engines do not deal with this the same way, since generating electricity through the alternator is generally treated as a byproduct, and range is almost unaffected by the condition of the aircraft's electrical system. Secondly, I'm curious as to why the sole choice of pusher configurations for this test. IIRC, one of the reasons that the pusher configuration is relatively rare in aviation is that clean airflow over airfoils generates more aerodynamic forces (i.e. lift OR thrust, depending on the aircraft), so putting pusher props into already turbulent airflow results in a more efficient wing , but worse output from the powerplant. I'm kind of curious how your results pan out if you include A: Pusher vs tractor configurations, and B: Ducted fan operations in similar and alternate setups, as again, IIRC, ducted fans are less affected by turbulent air, and act as small scale surrogates for turbine engines. But I'm just ranting at this point. Like I said, I'm a mechanic, so I prefer sticking to tried and true, and letting new technologies prove themselves instead of jumping on the early adoption train. Seriously, props on asking a question and trying it out.

Top notch stuff! love the scientific content, innovation and humour. One of the very (very) few channels on my 'must watch' list. Cheers!

A one engine out emergency would be interesting, that's why they don't do it unless you're the bell and can run both props from one engine if needed

Fascinating! I'm going to show my STEM group this because it's such a good lesson, thanks for uploading it!

Loved the video. Also I’m sure one of the reasons companies have stayed away from the wingtip engine configuration is with engine failures. It may provide great numbers in efficiency, but the cost of one engine failing means the other engine is basically useless. There would probably be too much yaw the allow the plane to fly straight.

Great work you did there. I’m looking forward to the solar plane!

I found it interesting that it increased the efficiency at all. Thanks for the video! Can’t wait for the conclusion of the project!

The noted improvement of efficiency is with the motors in pusher configuration; what improvement would you get with them in tractor? Put the props just ahead of the leading edge and rotating against the usual direction of wingtip vortices.

Shots of test mission (from quad?) are so beautiful!

Fantastic. Love it. Very interesting implementation of the placement of motors

congratulations 👍🏼🎊 please go ahead with this kind of projects and videos. And we are all looking forward to see some solar plane stuff together with Daniel from rctestflight