St. Phatty
Active member
This is something I've been thinking about for about 5 years.
My leaf-blower is a Hitachi with a green case and they say it blows at "150 miles per hour."
I tested it on a 45 gallon trash bag, it filled it up in less than a second. Way less.
I think it is blowing about 200 gallons per second. 25 cubic feet.
So those are the basic facts, and without going into something I suck at like differential equations, I would like to see if I could achieve flight using 3 leaf-blowers.
One on each wing, which is attached to your arm, and 1 or 2 on your back.
So if I ever did build this I want to make sure, it might be a little crazy, but I want it to work.
In order to get from Stoner Thoughts to bonafide aeronautic concept, I was thinking I could figure out the momentum/ impulse of the air coming out of the 3 leaf-blowers, and hopefully compare that to some specs for a small airplane.
weight of air at STP
1.225 kg/m3
https://www.google.com/search?q=weight+of+air+at+STP
m3 = 27 cubic feet. OK so, 25 cubic feet, 27 cubic feet, close enough. I will call it 3 pounds of air @ 120 miles per hour. = 360 pound-mph. That's per leaf-blower, with 3 you get a momentum/ impulse of 1080 pound-mph.
Since I weigh 180 pounds, That imparts an velocity of 6 miles per hour, to get the same 1080 pound - mph.
For take off and landing gear, quality roller skates.
https://www.google.com/search?q=thrust+small+airplane
https://www.google.com/search?q=Specific_impulse+small+airplane
https://en.wikipedia.org/wiki/Specific_impulse
Search terms -
incremental momentum small airplane
You know I could just build some airplane wings and put on my roller skates and experiment. I think that's how some crazy country projects get started, just a hunch, no solid math to confirm it.
Which could end up with me needing hospital care so then I would probably contract CoVid19.
So I think it's better to noodle it out. I am pretty sure that knowing how much weight the leaf-blower is moving and at what speed is enough to answer the question of "will it work" - but you need for aeronatics to figure it out, than I have.
I am pretty damn sure it would work.
As it turns out, airplanes are not calibrated in terms of leaf blower units.
So that's what I think about when I smoke pot sometimes !
And to be realistic, I think I might need to know the actual THRUST of the leaf-blower. which means building a simple fixture, with a pulley and a bucket of water for weight.
So then I did a search, "how much thrust for a goddamn small airplane"
well, here's a fact -
A 747's engines produce a quarter of a million pounds of thrust.
747's maximum takeoff weight ranges from 735,000 pounds
So 1 pound of thrust for 3 pounds of weight. If I have Boeing Quality wings (from before the merger with McDonnell Douglas, because then Boeing and Quality went in 2 separate directions).
I weight 180 pounds, with gear like WINGS and 3 fvcking leaf-blowers ... the leaf-blower weighs 9 pounds, 180 + 27 + 33 pounds, 33 pounds for clothes + wings + "Gear".
240 pounds total
I NEED 80 pounds of thrust.
I think I need more leaf-blowers.
Maybe with 5 leaf-blowers. If you hold a leaf-blower in your hand - can you get 15 pounds of thrust out of it ?
I think it would be fun to have a sports team that races people sized airplanes at tracks like Sears Point.
My leaf-blower is a Hitachi with a green case and they say it blows at "150 miles per hour."
I tested it on a 45 gallon trash bag, it filled it up in less than a second. Way less.
I think it is blowing about 200 gallons per second. 25 cubic feet.
So those are the basic facts, and without going into something I suck at like differential equations, I would like to see if I could achieve flight using 3 leaf-blowers.
One on each wing, which is attached to your arm, and 1 or 2 on your back.
So if I ever did build this I want to make sure, it might be a little crazy, but I want it to work.
In order to get from Stoner Thoughts to bonafide aeronautic concept, I was thinking I could figure out the momentum/ impulse of the air coming out of the 3 leaf-blowers, and hopefully compare that to some specs for a small airplane.
weight of air at STP
1.225 kg/m3
https://www.google.com/search?q=weight+of+air+at+STP
m3 = 27 cubic feet. OK so, 25 cubic feet, 27 cubic feet, close enough. I will call it 3 pounds of air @ 120 miles per hour. = 360 pound-mph. That's per leaf-blower, with 3 you get a momentum/ impulse of 1080 pound-mph.
Since I weigh 180 pounds, That imparts an velocity of 6 miles per hour, to get the same 1080 pound - mph.
For take off and landing gear, quality roller skates.
https://www.google.com/search?q=thrust+small+airplane
https://www.google.com/search?q=Specific_impulse+small+airplane
https://en.wikipedia.org/wiki/Specific_impulse
Search terms -
incremental momentum small airplane
You know I could just build some airplane wings and put on my roller skates and experiment. I think that's how some crazy country projects get started, just a hunch, no solid math to confirm it.
Which could end up with me needing hospital care so then I would probably contract CoVid19.
So I think it's better to noodle it out. I am pretty sure that knowing how much weight the leaf-blower is moving and at what speed is enough to answer the question of "will it work" - but you need for aeronatics to figure it out, than I have.
I am pretty damn sure it would work.
As it turns out, airplanes are not calibrated in terms of leaf blower units.
So that's what I think about when I smoke pot sometimes !
And to be realistic, I think I might need to know the actual THRUST of the leaf-blower. which means building a simple fixture, with a pulley and a bucket of water for weight.
So then I did a search, "how much thrust for a goddamn small airplane"
well, here's a fact -
A 747's engines produce a quarter of a million pounds of thrust.
747's maximum takeoff weight ranges from 735,000 pounds
So 1 pound of thrust for 3 pounds of weight. If I have Boeing Quality wings (from before the merger with McDonnell Douglas, because then Boeing and Quality went in 2 separate directions).
I weight 180 pounds, with gear like WINGS and 3 fvcking leaf-blowers ... the leaf-blower weighs 9 pounds, 180 + 27 + 33 pounds, 33 pounds for clothes + wings + "Gear".
240 pounds total
I NEED 80 pounds of thrust.
I think I need more leaf-blowers.
Maybe with 5 leaf-blowers. If you hold a leaf-blower in your hand - can you get 15 pounds of thrust out of it ?
I think it would be fun to have a sports team that races people sized airplanes at tracks like Sears Point.
