Human Powered Flight

Homebuilt Aircraft & Kit Plane Forum

Help Support Homebuilt Aircraft & Kit Plane Forum:

Tiger Tim

Well-Known Member
Joined
Apr 26, 2013
Messages
5,088
Location
Thunder Bay
Could ground effect be the solution...it is still flying isn't it ?
Has any human powered aircraft ever left ground effect? Given their enormous spans I’d think ground effect already is the solution and always has been.

I’d be curious if the last two Kremer prizes (which I believe are centred around speed) could be won with some sort of hybrid electric rig. For example the first half hour of the marathon would just be pedalling in place to charge a battery or other energy storage device, then release the brake and fly 52mph on the stored energy plus pedals for the last half hour. In my head there ought to be slightly less energy available due to transmission losses but perhaps that could be countered by not having to have an airframe to meet the needs of so little sustained power as we’ve seen to date.
 

Bob H

Active Member
Joined
Jun 9, 2022
Messages
25
When Bryan Allen was pedaling across the Channel, the support crews had boats on the water to pick him up should he lose his ability to power the plane. He was flying at ~30' above the water, calculated to be optimum. As he got around 2/3 across, his energy level decreased and he began to gradually lose altitude. The rescue teams were right under him, ready to grab the plane and get him out. But he found that when he got about 5' above the water, the pedaling got easier because of ground effect and he was able to complete the flight.

The team got help from unexpected sources. The Channel has very busy shipping traffic. As he was half-way thru the flight, spotters for ship traffic saw an oil tanker coming along and figured it would intersect the flight. They somehow managed to contact the ship's Captain and he graciously slowed the ship down so Albatross could pass without wake-turbulence damaging the plane. The success of the project was full of lucky circumstances.
 

Sraight'nlevel

Well-Known Member
Joined
Nov 4, 2021
Messages
464
I remember this incident from the vids...he almost scooped the water.

 

Attachments

  • brian.jpg
    brian.jpg
    30.4 KB · Views: 1
Last edited:

goney3

Well-Known Member
Supporting Member
Joined
May 5, 2021
Messages
45
Location
Lompoc, CA
Has any human powered aircraft ever left ground effect? Given their enormous spans I’d think ground effect already is the solution and always has been.

I’d be curious if the last two Kremer prizes (which I believe are centred around speed) could be won with some sort of hybrid electric rig. For example the first half hour of the marathon would just be pedalling in place to charge a battery or other energy storage device, then release the brake and fly 52mph on the stored energy plus pedals for the last half hour. In my head there ought to be slightly less energy available due to transmission losses but perhaps that could be countered by not having to have an airframe to meet the needs of so little sustained power as we’ve seen to date.
A German company (Schaeffler) created a "ride-by-wire" system that can generate electricity at the pedals and transmit that electricity to a motor. This could open the door to unique design possibilities and cut down on weight from mechanical chains/pulleys. I imagine the electric motor (while not very powerful ~250W) could spin at higher RPM's that are unable by a mechanical motion. Could this help?

From the article below: "5% less efficient than chain drives"

 
Last edited:

Sraight'nlevel

Well-Known Member
Joined
Nov 4, 2021
Messages
464
A German company (Schaeffler) created a "ride-by-wire" system that can generate electricity at the pedals and transmit that electricity to a motor. This could open the door to unique design possibilities and cut down on weight from mechanical chains/pulleys. I imagine the electric motor (while not very powerful ~250W) could spin at higher RPM's that are unable by a mechanical motion. Could this help?

From the article below: "5% less efficient than chain drives"

It is outstanding when using also solar....or batteries...or both.
 

goney3

Well-Known Member
Supporting Member
Joined
May 5, 2021
Messages
45
Location
Lompoc, CA

Sraight'nlevel

Well-Known Member
Joined
Nov 4, 2021
Messages
464
5% loss ok...but you have to have two electric motors/generators...so there is also a 5 kg weight penalty.
 

Sraight'nlevel

Well-Known Member
Joined
Nov 4, 2021
Messages
464
Has any human powered aircraft ever left ground effect? Given their enormous spans I’d think ground effect already is the solution and always has been.

I’d be curious if the last two Kremer prizes (which I believe are centred around speed) could be won with some sort of hybrid electric rig. For example the first half hour of the marathon would just be pedalling in place to charge a battery or other energy storage device, then release the brake and fly 52mph on the stored energy plus pedals for the last half hour. In my head there ought to be slightly less energy available due to transmission losses but perhaps that could be countered by not having to have an airframe to meet the needs of so little sustained power as we’ve seen to date.
That is the point exactly...they remain in ground effect, but they look anything but WIG crafts.
 

speedracer

Well-Known Member
Joined
Feb 4, 2020
Messages
390
I remember this incident from the vids...he almost scooped the water.


Brian Allen was also a hang glider pilot. I flew with him at the World Hang Glider Championships at Vancouver BC around 1980. He was a very modest, approachable guy. I should have gotten his autograph.
 

henryk

Well-Known Member
Joined
Mar 8, 2010
Messages
7,412
Location
krakow,poland
-Taras Kiceniuk was invented many modes of soaring ,recovering energy from nonstationary air flowes...

-Witold Kasper was observed another soaring mode="DYNAMIC soaring"
on His tailles glider BEKAS-N .

(possibility of soaring in athermic wheather, long distances on low altitude,
when horisontal gusts exists !)
 

Bob H

Active Member
Joined
Jun 9, 2022
Messages
25
A normal metal bike chain was too heavy for the Albatross so the team came up with a novel idea that used a Kevlar thread and a series of beads attached or knotted to the thread that were pitched to match the sprocket teeth. The Kevlar took the tension loads and was flexible and super light. I never saw the Kevlar chain so I don't know how they knotted the beads or what the beads were made from; just remembered the clever concept was built and worked in 1978.
 

Sraight'nlevel

Well-Known Member
Joined
Nov 4, 2021
Messages
464
I think that statement alone could be brought out any time someone thinks human powered flight could be easy or commonplace.
I think there a fewer HPA pilots than there are astronauts.
There are also very thin chains available today that are lighter.
 

nerobro

Well-Known Member
Joined
Nov 6, 2011
Messages
1,128
Location
Northern Illinois
I think there a fewer HPA pilots than there are astronauts.
There are also very thin chains available today that are lighter.
There may well be... but I think that may be more about the availablity of the airplanes than the number of people who could do it. As noted, the entire peloton of the TdF could fly human powered planes quite well. Horsepower wise.

About chain, not in comparison to kevlar thread there isn't.

I bet there would be a business in having a field where people could sprint little planes up to speed and get useful hops.
 
Top