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Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by jedi, Jan 27, 2018.
It doesn't pay well enough for me.
A famous aviator once explained to me how modern aviation was shrinking the world to just a fraction of its former size. He then demonstrated how a skilled pilot could still hit it.
That is is the job of a test pilot and I strive to be good at it. It is wise to treat every flight like you would a test flight.
Here are some numbers I worked up for the Go Fly competion. They were previously posted to the EAA web site.
The UL strip is a strange place to post a Boeing Go Fly proposal (http://goflyprize.com/) but here it is as I see no other place for a true experimental aircraft design discussion.
Since the HBA sight is down as noted in the Hangar Talk section I am posting the following here. The proposal does qualify as an ultralight with the 254 pound empty weight UL limitation.
As Phase I of the Go Fly completion is nearing completion I would like to publish some ideas and observations for the entertainment of the many HBA critics. Go ahead and make your negative (or positive) comments. Check my math and fire your arrows. English to SI unit conversions are approximate.
Taking the 8 foot max dimension into account I have assumed a powered lift vehicle for the apparent VTOL or near VTOL requirement to operate within the 30 foot diameter 12 foot high cylinder. Furthermore a 200 pound minimum useful load is specified. Generally an aircraft that can lift its own empty weight is considered a good design so I made the assumption that a 250 pound empty weight and 500 pound gross weight would be a reasonable starting point. I am proposing to enclose the lift fans in an 8 foot diameter circular duct for safety and noise constraint reasons. Configuration study CAD drawings are available.
With these figures in mind I came up with the following specifications for standard day sea level operation.
Go Fly Entry Proposal J-1
Empty weight 250 pounds
Gross weight 500 pounds
Duct Outside diameter 8 feet (2.4 meters)
Duct area 50 sq. ft. (4.6 sq. meters )
Duct loading 10 pounds per square foot (50 kg/sq. m)
Duct inlet area 50 sq. ft. (4.7 sq. m)
Duct exhaust area 33 sq. ft. (3 Sq. m)
Hover downwash velocity 55 mph (25 m/sec.) -Assume uniform steady flow.
Hover power loading required 7 pounds / hp (1.8 kg/Watt) -Asssume100 % hp to thrust efficiency.
Hover power required 72 hp (54Kw) -Asssume100 % fan efficiency and zero duct loss.
Proposed rated power 100 hp (75 Kw) minimum for std. day S. L. operation.
Note: 150 to 200 hp (110 to 150 Kw) Max T.O. )(one minute) power desired for the proposed VTOL operation.
I am considering a 1/32 scale model to illustrate the proposed design. Some motor details and other design features are being evaluated. Additional information and suggestions are available. However, as others have concluded the likelyhood of success is problematical and therefore I do not anticipate an official design submission on my behalf. If any readers with a greater risk tolerance wish to advance the cause I welcome additional discussions.
On Ausust 1, 2018 GoFly / Herox / BOEING (the big sponsor) deleted the Forum wherein the contestants of the GoFly / BOEING contest presented their opinions and their complaints.
GoFly’s / BOEING’s best response to contestants’ questions, was to shut down the annoying forum . . .
Each one of the contestants has paid 250 or 500 USD to GoFly / BOEING.
In return, all they took from GoFly / BOEING is the list with the ten winners.
No scoring, neither ranking, neither justification from the "97 judges"; just the ten winners alphabetically.
Take a look at http://www.pattakon.com/GoFly/index.html wherein some of the Open Forum Discussions have been “partially” saved and presented:
IS BOEING TRAPPED? : http://www.pattakon.com/GoFly/IS_BOEING_TRAPPED.html
20 minutes OR 20 miles? - Page 1 : http://www.pattakon.com/GoFly/20_minutes_or_20_miles.html
20 minutes OR 20 miles? - Page 2 : http://www.pattakon.com/GoFly/20_minutes_or_20_miles_Page_2.html
20 minutes OR 20 miles? - Page 3 : http://www.pattakon.com/GoFly/20_minutes_or_20_miles_Page_3.html
Note: the “20 minutes OR 20 miles” thread had in total 11 pages.
Design Discussion - Page 3 : http://www.pattakon.com/GoFly/Design_discussion_3Page.html
Design Discussion - Page 4 : http://www.pattakon.com/GoFly/Design_discussion_Page4.html
Design Discussion - Page 5 : http://www.pattakon.com/GoFly/Design_discussion_Page_5.html
Debating Results of Phase I : http://www.pattakon.com/GoFly/Debating_results_of_Phase_I.html
The above discussions are indicative and show the appreciation, the trust and the confidence of the contestants for the GoFly / Herox / BOEING contest.
When you have time to spend, read the http://www.pattakon.com/GoFly/Posts_to_GoFly_Forum.htm and give your comments / questions.
Manolis! Glad to hear from you. I was worried about you. Have you been flying the Portable Flyer?
He's posting, what do you think?
Seriously, I am not too surprised that this seems to be ending in tears. I have to admit, I was expecting bodies, though.
Jedi. I roughed out an annular fan design, ran the numbers and quickly decided that I lacked the required 50lb steel cahoneys to try flying it...
Really would have expected more professionalism from this, even if I admittedly believed the competition was not completely above boards.
Sorry about that. I would lend you one of mine but my wife says no way!!! :ban:
I’m not overly surprised they shut the GoFly forum down. Just imagine the Blackfly thread here but with some posters actually having money and effort invested in it or its competition. That would get real nasty real fast.
What about the competition itself, is it still on? I haven’t been watching too closely but my understanding was round one was to determined me which concepts got funded to continue to round two.
That was my impression also, but I read on their site that one can still enter by Dec. 8th deadline and that participation in phase 1 was not required. It seems that was just design awards,....interesting, but I would have hoped for more variation in creative thinking in all the winners.
Hello Victor Bravo.
"Really would have expected more professionalism from this"
Quote from http://www.pattakon.com/GoFly/Posts_to_GoFly_Forum.htm (wherein they are saved my posts (from 15 June 2018, to 1 August 2018) to the deleted forum of GoFly):
Hello Mokren. (9 July 2018)
To participate in the rest phases?
Only when BOEING will decide to take over and to turn this challenge to a decent and transparent one.
The credibility GoFly earned so far is for laugh.
They pretend their goal / vision is to foster thinkers and tinkers make people fly.
The 250 USD I paid them is nothing, but make me a sucker: that some guys, hiding behind a big name (BOEING), have deceived me is frustrating.
It is a shame for BOEING to continue as the big sponsor of GoFly.
To put it simply, what I purchased with my 250 USD is the following info:
“You are not in the ten winners of the Phase I. Period.”
Neither scoring, nor ranking, nor justification of the decision, nor a clue for the weak points the judges find in my solution, nothing at all.
Just that I am not in the ten winners of phase I. . .
And now they try to trap again the contestants with cheap “tricks” of the kind:
"Dear contestant, in order to get a REVIEW of your Phase I submission, you have first to register to phase II; and in order to register to phase II, you have, among others, to create a company, to pay insurance fee, to pay “team” fee and to give equity rights to GoFly.”
The trick / the cheating is double.
By “REVIEW” they do not mean the “fully justified resolution / verdict / decision of the judges”.
They just mean “a” review from “some” guy who is nominated as a “mentor”.
As you remember, they promised to give the scoring and ranking, and they never deliver.
Would you characterize the guy who thought the above “double trick” as a “decent guy whose vision is to foster people fly”, or as a scam?
End of Quote
You don’t need them. Build your machine, fly it, and, if it does what you say it will do, you will be very successful.
Here are the moving parts of the OPRE TIlting 2-stroke engine:
The above tilting valves have "rectangle" shape for the shake of the easy / accurate manufacturing with a lathe.
And here are two youtube videos of the engine (manual cranking).
"Welcome back my friends, to the show that never ends!" - Emerson, Lake and Palmer
Boeing has a new contest... it's called "Fight the computer to get that nose up!"
If you win, you live
Somebody needs to snip the wire to the idiot sensor.
First cast OPRE Tilting parts:
Hopefully they will withstand the loads.
For more: https://www.pattakon.com/GoFly/index.html , https://www.pattakon.com/pattakonPatTol.htm, https://www.pattakon.com/pattakonTilting.htm
Separate names with a comma.