Beta technologies Ava

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jedi

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The channel-wing idea is not so much the point here but rather that the fan inflow generates wing lift without forward airspeed. I assume with distributed propulsion at the trailing edge you could achieve the same effect.
Agree. But you could look at the Channel Wing as half of a ducted fan. The full circle fan would also increase the vertical propeller thrust. How the two would compare is a good question. Also what would a ducted fan with sweep to the duct leading edge do to change flow patterns and how would it effect forward flight performance.

Some model work would answer lots of questions.
 
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Andy_RR

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Interesting stuff, except the pitch is a bit mangled:

After getting acquainted with our presentation, some experts will may
mistakenly think that they themselves, without us, can create unmanned aerial
vehicle vertical takeoff and landing (UAV VTOL) with propulsor of oscillatory type.

This is an illusion.

Oscillatory aerodynamics - is a new, poorly studied area of aerodynamics
(we know this area better than anyone), and the principles of R & D - is an
innovative and unknown for usual aviation scientists and designers.

These experts are not able to create a super-efficient UAV VTOL, and they
only will bring huge losses to the company.
I think this is long on obfuscation and short on demonstration. As they say, seeing is believing but I have an uneasy feeling reading through all this stuff on the vortexosc.com site that a) there definitely is something there and b) that it is lubricated with a healthy dose of snake oil. If Sorokodum et al are seriously looking for investment they need to do a bit more explaining and perhaps come up with a simple demonstration rig.
 

Andy_RR

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Melbourne, Australia
Re: Tailless Aircraft - Reflex and other design issues

All of the above is premature until the problem to be solved is clearly defined. Is it a more useful GA aircraft, an inexpensive sport plane, a traffic avoidance commuter, a longer range roadable aircraft or all of the above.
I think the problem is self explanatory. Currently with fixed-wing aircraft (described as general aviation aircraft) there is a yawning gap in capability between the apron and stall flight speeds which is overcome by a relatively dangerous high-speed dash down a protected area of real-estate. On top of that, noise is usually unaddressed and therefore high aircraft movements become the targets for NIMBY action. Helicopters don't improve on this much except to add a high skill requirement to fly them and are equally dangerous and obnoxiously noisy to bystanders to relegate their operation to the previously prepared real-estate for fixed-wing flyers. None of it is particularly useful or affordable for the average punter living in a relatively congested environment.

I think the holy grail of the eVTOL proponents is a quiet and safe device that makes point-to-point air transport available to the masses, or at least more widely available. What this actually looks like and whether it can really be done are both clearly wide open issues.

The "Beta Technologies Ava" and many of the current crop of electric lift fans tend to be towards solving the "traffic avoidance commuter". As has been frequently pointed out in other threads this can be and in fact is done with current technology helicopters. There should be a detailed discussion of how the proposed electric lift fans will solve the helicopter problems of limited landing areas, operations in existing airspace structure, and high cost including fuel burn/electric/battery limitations.
I think the general attraction to electric propulsion is the ready ability to control the lift force vector electronically compared to, say, a conventional helicopter. The skill level required to pilot a conventional helicopter is one factor which puts it out of reach of most people. As https://www.youtube.com/watch?v=-05wY41ht1s shows the power consumption of a helicopter is also a bit of an issue. I'm not exactly sure how to get past this, but efficient wing-borne flight to improve range also means carting a whole load less batteries around which directly impacts on hover power requirements. The attraction of transforming aircraft of some type is thus obvious.

I am not convinced that any of us on HBA are interested enough to seriously discuss many of these issues.
You might be right, but I'm quite interested in the eVTOL scene enough to be doing and sketching my own concept so I'm happy to hear other people's ideas, especially on a thread dedicated to discussing a recent eVTOL entrant. At some point I'll probably publish my concepts here too and then stand well back...
 

henryk

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Interesting stuff, except the pitch is a bit mangled:



I think this is long on obfuscation and short on demonstration. As they say, seeing is believing but I have an uneasy feeling reading through all this stuff on the vortexosc.com site that a) there definitely is something there and b) that it is lubricated with a healthy dose of snake oil. If Sorokodum et al are seriously looking for investment they need to do a bit more explaining and perhaps come up with a simple demonstration rig.
http://www.vortexosc.com/modules.php?name=Content&pa=showpage&pid=267

=see 1:25 min...oscillating propellers thrust measure stand=thrust force 0.2 kG/2 W !
 
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