I WANT ONE - NOW!!!!!
Forget saving up for the Porsche - I really, really, really want one!
A radical autogyro jump-copter "Personal Air Vehicle" able to make vertical takeoff and landings but cruise in winged flight like an aeroplane has achieved a key flight-test milestone. The Carter PAV takes off for a test flight. Credit: Anita Infante Wings optional The Personal Air Vehicle (or PAV) is a new design from …
I'd be a bit more patient - autorotating is essentially a semi-controlled crashlanding! Unless the autopilot has a nifty new trick for making autorotational descents, this will not be an easy craft to land. You only get one shot at dumping the kinetic energy into lift, so if you adjust pitch too soon or too late it becomes a crashlanding. It's also not something you can usually recover from and go round for a second attempt. There's also the factor that most pilots seem to like a little bit of forward motion on their autorotates to allow them to see where they're going to land/impact, so it looks like true vertical landings are unlikely without a lot of practice and skill. TBH, I can't see why someone can't design it so they have a gearbox (or electric drive) drom the main engine to provide power for take-off and landing lift for the main rotor, keep the wings, and simply switch to auto-gyro mode in flight. Torque could be countered by two sets of contra-rotating rotors.
Probably because conventional planes (and autogyros) tend to be faster and more economic than helicopters. Helicopters come into their own in situations like cities, where landing sites may be as small as the roof of an office block, but conventional planes are better for flying long distances as long as you have a landing strip at each end of the journey. One of the holy grails of chopper design has to been to produce an "Airwolf" type flying machine that has the best of both (except without the Mach 2, missiles, and definately without Jan Michael Vincent, though I might keep the themetune!). This actually does look quite feasible, it's just the one-chance landing style that makes me nervous ("Oh crud, that unexpected sidewind has pushed our descent towards the edge of the rooftop landing pad, and I don't have a means to add power and go round for a second attempt like I would in a chopper, I'm just going to bounce between two buildings and kill anyone on the city street below....."). If the result is the FAA, for example, refuses to let the design use city landing pads then it is unlikely to replace many of the private and commercial helicopters and hence may have limited commercial success.
the tech apparently scales to 747 size.
also as the only other company making this tech is AAIs uavs and they havent made one yet...
lets put that into perspective replace SCR gyro with fattest city.
just imagine houstin is not only americas fattest city(it was last I looked) but is INFINATELY fatter than any other city and is on track to get 100x fatter with no forseeable technical dificaulties.
I think this not only ticks the texas bigger box but by some way.
Oh yeah you guys who want one, get to the back of the queue.
wheres the "everything is bigger in america" icon, i'll have to go with paris, i heard shes bigger in america.
Carter has built and tested jump-copter aircraft before, but they seemed to lack one major PAV attribute: that of being easy to fly. Even experienced ex-military test pilots have suffered mishaps at the controls of Carter craft in previous years. According to the company, this has been addressed in the new PAV:
Hmm - I read somewhere that gyrocopter pilots consider helicopter and (mil) test pilots to be folks who crash ag's because of the wrong reactions. It seems a helicopter pilot automatically does the opposite to a ag pilot in a "stall" - which is where most mil test pilots end up pushing the envelope and due to wrong reactions end up dying with the machine taking the blame...
When the pre-rotor gets disengaged, and the disk starts to 'bite', where does that extra air go? Surely downdraft on the wings, doing the opposite of the intention.
If the rotor is tilted forward to reduce this, it's blowing straight on the tail...
Aerodynamics must've been a helluva challenge.
I'd disagree with one part of the article.
Vertical takeoff -aka jump-start - has been possible, as Carter themselves have demonstrated. Would'nt catch me in the thing, tho'.
Last 20 seconds - I wouldn't call that a controlled crash...
Unpowered rotating wings are not a new idea, in fact they predate the commercial development of the powered-rotor 'copter.
From what I understand -having examined a few autogyros at an aircraft maintainer's hangar some years back- they are easier to fly than a regular 'copter (no collective lever, and no rotor-induced yaw to complicate the control-inputs) but do have one or two nasty vices that powered rotors don't have.
The advantage over fixed-wing is that by running-up the rotor on the ground, a very short takeoff run is possible. Likewise on landing the lift from the rotor is maintained down to almost zero airspeed, making for a short roll. The things they can't do, of course, are to takeoff or land vertically, or hover.
As for me, I'd love a fullsize one of these to go to work in:
-A black one, naturally.
Now, that would turn heads. ;-)
To be fair to Carter, they've never made a secret of the problems they've had with this, and there are a couple of YouTubes of their prototype crashing but, thankfully, not burning, posted by themselves.
The bit Lewis doesn't mention is that the rotor tip weights are made of depleted uranium, used because of its high density, therefore compact size.
What happens if these weights break loose, given metallic uranium's useless lattice structure which famously powders if impacted hard enough, and that "depleted" uranium is still quite radioactive, and reasonably toxic like most heavy metals when ingested.
I know that the US, Israeli, and UK governments argue that powdered depleted uranium is a positive boon to health, for legal reasons, but I could see that many might prefer their neighbors not to be spinning a couple of large lumps of the stuff, mounted on long sticks yet, around at high speed within a stone's throw of their houses.
Do the Clarksons of the world really represent a large enough market?
By coincidence an old friend developed recently a new bad habit and made last summer a pilote license for autogyros. One year later he is the proud owner of such a thingy and finally dragged me to the hangar to show off with his rickety thingy.
Well, so what?
Well, there were about four or five autogyros in the hangar (from at least three different manufactureres, one selfbuild (!)) and they ALL had either an electric starter motor on the rotor shaft or - even better - the more expensive models had a belt-drive system to temporarily divert power from the propeller shaft to the rotor. I asked for what this is used, as it was clearly not powerful enough to produce significant lift as it's done in a helicopter.
"Well" he said "that's for accelerating the main rotor a bit to shorten the take-off distance. They all have that."
Guess Carter lost exclusivity on that assessory of an autogyro about sixty years ago...
Using the same props for takeoff and subsequent level flight just seems a smarter way to do it. The Pogo's only real flaw was the problems landing whilst looking over your shoulder, but the availability of modern, computerised stability systems, miniature cameras for looking down, and maybe even auto-landing systems, all make the Pogo look viable. And it certainly looks a might cooler than Carter's attempt.
As an ex-military helicopter pilot who remembers doing many, many autorotational landings during training and on-going pilot tests the memory of them still gives me the sh!ts. Autorotational landings are a one shot deal - you get it right or you crash, there is no inbetween conclusion. The crash may simply damage the aircraft if you get it mildly wrong or kill you if you get it very wrong - I couldn't face that on every flight. I still remember the feeling in my stomach and the loosening of my bowels as the instructor rolled off the throttle or reached for the High Pressure fuel cock...
Every phase of flight in a gyroplane is an autorotation, not just landing, since the rotor blades are not directly powered during flight, but rather rotate like a pinwheel in a breeze. The main engine, via thrust from its propeller, pushes the rotor blades through the air creating lift. Because there is no torque to deal with as with the driven rotors of helicopters, a gyroplane is extremely easy to fly. A gyroplane flies much like a highly manueverable fixed wing aircraft, although much more stable due to the gyroscopic effect caused by the spinning rotor blades.
The exception in this case is the jump takeoff mode, which is a one shot deal to get right because the rotor blades have a finite amount of rotational inertia stored from being pre-spun to flight speed by the small auxilliary engine. Igor Benson developed a prototype jump-takeoff version of his popular B-8 gyrocopter back in the 1970s and I observed him from a short distance perform a jump takeoff at a small airshow back in the late 1970s. While he performed it expertly, the look on his face revealed that he was concentrating 100%. Once he made it through to the forward airspeed phase, a matter of only a couple of seconds max and maybe 5-6 feet off the ground, he disengaged his two auxilliary rotor blade engines then lowered the nose slightly to gain airspeed quickly and zoomed off as normal. I'm sure this gyroplane will react similarly during jump takeoff mode and cause a similar 'pucker factor' for the pilot. After the transition to forward flight is achieved this gyroplane should be extremely easy to fly because of the inherent stability of autogyros.
How do I know this? While I was taking flying lessons to get my pilot's license for fixed wing aircraft back in the late 1970s I taught myself to fly a little single seat Benson B-8M gyrocopter and I flew it for years, along with a variety of other fixed wing aircraft. It was absolutely the most fun flying machine I've ever had the pleasure of piloting. I would much rather be at the controls of a gyroplane when the main engine quits than a fixed wing aircraft. Both will glide, but the gyroplane has the ability to land at very nearly zero forward airspeed and cannot ever stall. Because of this you can successfully 'dead stick' land it just about anywhere because you just don't need much room. A tiny parking lot or field will suffice; even someone's front or back yard will do in a pinch. You certainly can't say that about any typical fixed wing aircraft. And emergency engine out landings in a helicopter are the most difficult to execute successfully as there just isn't much margin of error.
All that said, I'm really not sure of the purpose of this design except as maybe a proof of concept. It may be able to perform a jump takeoff but will still require a clear area ahead to transition to forward flight and build up enough forward airspeed to clear obstacles in its path. Also, had they incorporated short wings and low drag in flight storage of the rotor blades during high speed flight it would make much more sense. It also boggles the mind why they didn't incorporate a flex cable drive from the main engine to spin up the rotor blades thus eliminating a complete auxiliary drive engine system. The flex cable idea was a common option way back when and I fitted one to my gyro and it performed flawlessly. It has the ability to transmit much more torque to spin up the rotors than some tiny auxiliary engine. And I've used both.
- Paris, because she knows how to achieve maximum lift under any circumstances!
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