Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by lear999wa, Mar 31, 2013.
Some innovative stuff talked about in this podcast. What are your favorite parts?
Re: Rutan outa clue ?
That rule is only applicable to type certified motor gliders. There is no similar rule for experimentals.
Re: Rutan outa clue ?
It might not be a hard-and-fast rule for experimentals, but complying with it makes it much easier to convince the FAA's representative that your aircraft is indeed a motorglider and not just a powered airplane you're trying to sneak through the rule. If you're already on the FAA's radar like Mr. Rutan is, it's probably an even better idea.
As a former DAR I can tell you that the FAA or the designee will use the span loading equation to help determine if the experimental is certified as a glider or airplane.
Is there a hard number that separates the two?
7.b. Additional criteria for Powered Gliders.
(1) Powered fixed-wing gliders may be type certificated
under Section 21.17(b) if:
(i) The number of occupants does not exceed two;
(ii) Maximum weight does not exceed 850 kg (1874
(iii) The maximum weight to -wing span squared (w/b2
does not exceed 3.0 kg/m2 (0.62 lb./ft. 2
NOTE: These criteria originated from JAR-22.
Again...the rule only applies to type certified aircraft...factory built. Mr. Rutan has already certified one of his previous planes as a motor glider that did not meet the span squared criteria...the original Space Ship 1. N328KF Aircraft Registration
Read post #4 and #22 in this thread on motor gliders for more education: https://www.homebuiltairplanes.com/forums/soaring/8161-lsa-motorglider-concept-2.html
A misinformed DAR or FAA rep might make that mistake. A better understanding of the reg's will clear up the confusion.
I find it difficult to recognize favorite parts of this interview. Anyway what I find most interesting is how detailed he describes the Ski Gull. It does sound like Rutan have studied a lot of old NACA papers and maybe he have browsed this site too? It sounds like he have applied some of the ideas that have been floated here. If I remember correct, to have a pneumatic bladder between the fuselage and the planning bottom was discussed in some thread sometime.
Hmmm, has anyone ever seen Tunnels and Burt Rutan in the same room together? ... I'm just saying ...
Its not thinking outside the box but dispensing with the box totally and completely .You need to step completely away from your surrounds and put down all you know !! even to the point of change the people you associate with to see what you are missing out on and gain a fresh prospective of yourself and your surrounding's !! has anyone ever seen Tunnels and Burt Rutan in the same room together ?? it would never happen!!
Brilliant summary Tunnels, 10/10. Dare to adventure, dare to be laughed at - and you will be.
You won't have to change the people you associate with though, in short time most of them will walk away from you preferring the known and safe road, understandable.
The ski thing alone is not the compete answer !Its has to be included as a part of another scenario ! This where single mindedness is a major problem with ideas !
Looking at foils as an example, By them selves they are a fantastic invention but have a very limited speed range that they can and will work in !!,The Ski thing is the same , by its self its got limitation's and that where single mindedness is the problem !
The tunnels keep going on about since day one has lots of advantages And has been mentioned it can have a foil fitted that will ADD TO its usability ! It has Ski technology built In , People look but never see what's really there !
ski and Foils and tunnels combine are awesome and are being used for long time !!
The box is no where to be seem !! can you see it ??
Le prochain prototype de Burt Rutan
Burt does a lot of stuff out of the box, but I don't see the Ski-Gull as an out-of-box endeavor. It is just a smart collection of existing (past) design features to create a craft that is tailored to his mission.
I agree with BMCJ's assessment, but one thing I'd like to add is that Rutan has certainly not lost his ability to make really big claims. Yes he frequently meets these claims, to his credit and to his enduring iconic status.
But the magazine articles about this airplane usually quote him as saying ...' imagine going on an 8 month trip around the world never landing at an airport...' or something to that effect.
I'm sure Burt can design and build an airframe that will be tough enough to do that. Now... what kind of LSA or motorglider-qualified ENGINE will support that kind of an expedition? A de-rated PT-6 turbine... a low compression box stock Chevy 350.... a bank of ten Honda V-Twin generator engines stolen from my VP-21 supply room?
Remember, he's talking about going into the Amazon, and out in the Gobi desert, and probably the North Atlantic while he's at it. With the weight restrictions limiting the size and type of engine that is usable, an engine that has the reliability and repairability to pull off such a venture is not exactly commonplace. The old fashioned O-200, O-320 and O-360 will do that, and so will the O-470. I'm not convinced the 912 or 914 Rotax is simple and reliable enough to make Rutan's claim of a personal world explorer aircraft a reality for the common person..
Good to see back yard inventions still exist and with lots of string , wood and polystyrene and spray how can anyone see what's actually happening !!
Well, keep in mind that you could fly around the world more than 4 times on a thousand hours, and for a third the cost of the average American home... definitely not out of reach for many Americans. Although the area of a Venn diagram that overlaps between these people and those who are pilots may be much smaller.
I believe the engine has already been determined. May have some mods outside the OEM realm. Harrison Aero may pipe up here with more info.
Here's some more info that just came out (starts at 29:45)... AirplaneGeeks 350 Burt Rutan Is At It Again | Airplane Geeks Podcast
As far as the engine- it's been published online that it will be a turbocharged Rotax with excellent fuel efficiency.
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