VTOL hybrid flying car promises the skies The flying-car designers at Terrafugia may be behind schedule getting their first commercial model off the ground, but they're already talking up their next big idea: a four-person hybrid car with tilting engines that allow for vertical takeoff and landing, which could be in production by 2025. Terrafuiga TF-X VTOL flying car …
Even supposing the users manage to learn to fly safely (doubtful if bush pilots in Alaska are any indication) who is going to maintain them? Most people can't even jump start their own car anymore, much less properly torque a fastener or maintain crucial fluid levels, etc... See title.
I thought so too, but really, most people won't be getting one of these. Consider that the previous kit is in the order of $279K, much higher than the price of a standard light sport aircraft ($20K-$140K). So this is not that every muppet can go out and get a flying car, it's more of some rich people are going to get these as airplanes that they don't have to store at the airport anymore. Whether or not they should be flying is moot, as they already are in the air though other, cheaper craft.
Blain, I think you've hit that nail square on the head. This is something that the likes of Dean Kamen will have. If you have a quick look at his NH house you'll notice the south facing helicopter garage which likely counts as a home run in deep center field on the baseball diamond.
You might be able to afford one, but then you need to keep it maintained, this in turn will generate a mass of paperwork that no normal householder will want to deal with.
A minimum 53 hours of flying tuition, a number of exams to pass, including a radio licence, meteorology etc, then further training and exams for an IMC or IR to fly in cloud and regular checks. Renewal of licence every two years, medicals, and more frequent medicals as you get older.... Checks that make the annual MOT for your car look petty...
Heard it all before, it becomes a rich mans toy, a few are made and then the manufacturer goes bust.
A more complete reading of the article reveals "Under a deal with the authorities, Transition drivers will only need a sports license to fly, which only requires 20 hours of flight time and less exacting aeronautical knowledge. "
Still, have to agree that is will be nothing more than a rich man's toy at this point - but then much advancing, bleeding edge technology starts this way...
It still is a powered AC and has to land on an airfield, you can't just put it down on your lawn. I'm not so sure about the sports license either. Tilt rotor AC require a powered lift cert in the US and both, PPL and HPL, anywhere else. Add the cost for the license to the price of the "thing" and we're looking at +300K. A brand new, Garmin equipped, C-172 is 20K less, same is true for an R22 helicopter. The saved money could be spent on a real car, so you don't have to walk home. Imho, the whole "Flying Car" idea is Bollocks.
I believe that to the target market, the ability to mutter the phrase "why don't you come back to my place and I'll show you my flying car" is of greater value than the carplane itself, and well worth the ridiculous cost/contrived design.
Personally I don't see the appeal of a car that makes going around corners unneccesary.
The 'point' is in making a product that has an envisaged market.
There are always people out there who want (must have) the latest gizmo irrespective of the cost - what's so wrong with providing them with the objects of their desire?
If I had the money, space, acquired skilset then I'd be interested.
Sports license applies to the model currently in development, the new 20-year+ VTOL will likely need a different license. Maybe not anyone can land them on tehir lawn, but it would probably be licensed to land anywhere that a helicopter currently can. And I'm sure the rich folks who can affod it will probably be able to sneak in some space for a helipad on their ranch
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Firstly it was the Reliant Robin not the other way round. Secondly far from flying it was known for falling over going round corners as famously demonstrated by Blowhard Clarkson on Top Gear. No need for one of them to get airborne to crash and burn. In fact after a burnout to one, i've know everthing apart from the chassis & running gear / drivetrain being shoveled into a couple of dustbins. No TUV in them days.
I'd hate to see what happens when they try more than 10 degrees of bank on this aircraft.
I suspect when they run this past their aeronautical engineers the wings will be forced into a dihedral shape, the surface area will have to be increased, a larger vertical stabilizer with a boom or extended body for the elevators and hey presto it becomes a ...oh!
definite stability issues with that much anhedral. Kudos to writer about probable lack of driver/pilot competence, Bad enough seeing poor airmanship from trained pilots, let alone Joe Clot, fresh from snorting white powders and a recent ego stroke. One thinks that in this vehicle, computers over-riding wetware pilots is a good thing.
"Especially as it's designed to seat 4 Americans"
Yes but even the auto manufacturers aren't exactly honest about vehicle capacities, especially when it comes to SUVs and "Crossovers". They know it's for soccer moms who don't want to drive a minivan so when they say "seats 7" know that means 1 adult and 6 children since the cargo capacity is often around 1,000 lbs so they can keep the soft ride. Granted, it is getting better but most (all?) auto manufacturers still advertise on cargo volume and seats while never mentioning useful load so why should these guys be any different?
Whilst having the tilt rotors electric makes them mechanically simpler won't that mean that the thing has to lift a load of battery weight? would not IC based one be better sharing the same fuel tank as the main rear drive.
Also have they cured the battery aging? hate to see the results after 3 years when those VTOL engines run out of juice a lot quicker.
Still good luck to them!
You'll probably need to run the main engine for a few minutes to charge the lift-off/landing batteries before you go. Two electric motors and some batteries are likely to be lighter to carry round when they're not needed than two IC engines capable of lifting the thing. It's like Formula 1 KERS for aircraft.
The reason we don't all have a personal helicopter in our back yard are:
1 ~ They are difficult to fly. But this may be taken care of by advanced autopilots.
2 ~ VTOL needs a much more powerful engine than taking off an landing from a runway. Hence almost all helicopters use turbines, which are very costly due to the maintenance required. Also the mechanical transmissions used to transfer all that power from the turbine(s) to the rotors are very maintenance heavy. Terrafugia is proposing that they can get around these problems using electric motors... but if it was that easy then surely the military would already have gone down this route?
Combustion/electric drives are mainly used on systems where weight is no problem, such as railway locomotives, and to a lesser degree starting now on shipping. Not only are they heavier, but if power is critical you need to make up for the conversion losses between alternator input and motor output.
On a flying vehicle this seems to combine weight, complexity and inefficiency in all the wrong combination, but the makers hand may be forced by an inability to make the design work with a mechanical drive.
Diesel-Electric drive on ships has been in common use for a long time - at least 20 years.
Pretty much every new-build cruise ship is that way - the exceptions are the gas turbine vessels, which have - you guessed it - gas turbines to generate instead of fuel-oil diesels.
Also, the manoeuvring thrusters have been electric for much, much longer.
I know they're working on new ceramic engines, and I remember when people thought they'd never make unbreakable glass! Ah but guess where the pope stands behind. I would guess ceramics engines may be somewhat of an answer to lightweight future flight. Only thing is the engines need the strength to endure collision. Another question is will they all have black boxes?
I would think leaving out the props for autorotation (if big enough?) would be best safety practice. but then again, perhaps a craft this small could carry an airplane parachute? They are going to be needed, or at least some safety measure is needed. Helis usually have autorotation of some sort, planes have wings. We don't get many, even trained, pilots flying totally unrecoverable aircraft, do we? So it's something that needs to be in the design from the get go.
In some cases that non steerable chute will STILL be preferable to a human pilot, which may also crash you in to the side of tall buildings, mountains, trees or lakes depending on which way the wind is blowing, except with propellers still spinning at cruising speed.
Surely for the take-off you just plug it in. Magnetic connection from the cable to the car/plane means that as soon as you take off, the connection is broken, and off you fly. Landings are much easier than take-offs, as it's going up that takes effort - down happens automatically...
Hmmm. Perhaps there's a reason I'm not an aeronautical engineer.
As noted 1MW = 1341 hp, but we're given the 2 nacelle rotors are 600hp and the drive is 300hp anyway.
So (assuming the drive engine, which is 300hp) drives these for every unit of time the ascent process takes it needs to run (roughly) 4x that long to charge the batteries for the takeoff.
That's important because the longer that process the heavier the batteries get.
Note this hybrid drive concept is not quite as you might think. Mechano/electric/mechano conversion is highly efficient (it's the thermodynamic chemo/mechanical conversion that stuffs the efficiency). High speed generators and motors can be made very compact and eliminate both the huge gearboxes to step down the gas turbine to rotor speed of the Osprey and its monster cross coupling shaft.
It also help that it's unlikely they system will be designed to allow you to open the doors in hover and rappel to the ground, or offer covering fire while remaining in hover mode.
Note the rate the energy has to stored and dumped sounds more like a supercapacitor application, but I think their capacity Vs volume and mass is not quite up to it.
Is the SoA in batteries, motors, generators and power electronics in general up to it?
Maybe. Or close, and this is an area that where development (for other reasons) is moving quite fast. This architecture can leverage developments elsewhere in a way the Moller concept (high power to weight Wankels are pretty specialized) could not.
Could it be a money pit like Moller? Definitely. The fact they have not got their 1st model certified to fly does not encourage comfort. But (counter intuitively) the more complex power conversion may make the task simpler.
I'll wish them a (skeptical) good luck.
"It also help that it's unlikely they system will be designed to allow you to open the doors in hover and rappel to the ground, or offer covering fire while remaining in hover mode."
So a non-starter in the US consumer market, then?"
Sadly that rather disappointing performance is likely to put off quite a lot of the sort of potential customers with ready cash (as in by the duffel bag load) who might be interested.
When I was a boy, my dad worked for Bell Aerosystems and they were developing the X22A experimental version of what became the V22 Osprey.
The experimental version looked like a futuristic minibus with four large ducted fans tied to onboard turbines.
See http://www.aero-web.org/specs/bell/x-22a.htm
That thing had NO LIFT besides the fans (still doesn't have much) and when it lost power during flight trials it crashed like a stone.
The Osprey is a little better because there is at least "some" autogyro action from the MUCH larger rotors. They got rid of the ducted fans when it was determined they did not provide any advantage.
This is the closest thing to a flying VTOL "car" (as in carrying lots of cargo and passengers) that flew "successfully"
And another show from over 20 years ago promised to be able to hover-convert my old car for just $39,999.99 by 2015 but since that's less than 2 years away I can't see it happening either...
Besides, I don't have one cent shy of 40 grand burning a hole in my pocket so never mind the flying cars, I want my fracking hoverboard!
Googled supercapacitors.
The Russians reported at an international conference they were running buses solely on supercapacitors in 1995.
The storage capacity was about 30MJ, so enough for 30 secs of transition flight. A brisk process but not quite neck snapping (as long as nothing goes wrong).
No idea how heavy they were but not entirely impossible as a system architecture given the 18 years of further development in this area.
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