Aerospace Technology

It's an awesome idea but if you have to take it to an airport to take-off then it's probably not worthwhile.

You gotta start somewhere though and it's still pretty sweet.

Imagine the cost of having this thing repaired when some idiot texting on his phone while driving slams into you on the street. A fender bender on my car was over 2k just far the front quarter panel last time I had an accident.

Aircraft crashing into buildings?

No, never happen.

With the need for fuel consumption reduction, this is a toy for the rich that will be banned shortly. It is still illeal to fly any aircraft into a city zone without permission and this is not likely to change soon.

Fabulous. GA... When do we see your design?

Chris,

I am working on the engine, namely the hydraulic transformer. When? I know basically what the airplane (seaplane) needs to do. No configuration I know of that you would find at Oskosh or some airshow will do the job.

If I knew everything (plans were given to me) from here, it would take 3-5 years of man hours, or 6-10k hrs to one off a prototype. That is typical of hand built experimental airplanes.

Hi Chris,

I had an idea for a "flying car" and thought you may be interested
in getting your great design skills to illustrate it?

(If you find any money in it please remeber me!)

It's not particularly "new" but I thought you might like to play with it.
(the idea - naturally!)

Planes are cumbersome and ugly as cars, and cars are inpractical for flying.
So why force them together? The car is a passenger "pod" and the rest
of the "plane" (frame) can be left at the airport! (and collected / used later.)

Make a very light weight car (to drive on the roads) with such a design
as to drive in (plug in) to a wing structure (left at the airport or runway)

Simply, why drive around with a monkey on your back? If you don't have to!
Drive around, return to your airframe, drive into the "pod" slot, and fly away!

Any good?

jt.

Cool idea! I like that one. as for rendering, its hard to find enough time.. but I will post here if I can get something made. maybe if you had a quick paintbrush sketch to get me oriented to your basic features..otherwise I will have to make it up myself.

Chris

Your vehicle could easily be a motorcycle. Light weight and lots of power. Not as practical as a car but an easy fit.

Just the power and telephone lines that parallel most roads would spell doom for a flying car.

"High wing only, no low wing. You need to be able to clear parked cars with you wing."

Be real high wing as it has to clear trucks unless we are going to do away with ground freight or restrict roads to them. Make new roads to accommodate one or the other.

There is estimated 250 million vehicles registered in the USA. If 1% of the owners acquired this type car. If of these 10% are heading home at rush hour. That puts 250 thousand in the air at that time over the US. There is only about 5 thousand planes in the air in the world at any given time. Most of 250 thousand will be in heavily populated areas. Your work is intriguing but has any one looked at what a nightmare to control that will be and who will pay for the control infrastructure

Right you are. The FAA will not allow unmanned planes to fly without specific approvals. Not even for law enforcement agencies. What chance do you think flying automobiles have?

It's challenging for sure.. impossible no. The answer will be a new paradigm. like maybe the control will be in each vehicle, and communicating via gps satellite to other vehicles within its sphere of influence. the point is, this is going to happen eventually, and the supporting technologies will have to be developed. I think the onboard computer will do most of the driving. humans may have override,but there will definitely be next generatation onboard flight computers, realtime sensors for the vehicle in all directions, realtime connection with all other vehicles in a given sphere, with all flight data.. .like each vehicle being its own air traffic control center... the algorithms will negotiate with each other for flight positioning based a list of variables.

and I don't think the working solutions will have long wings.. it won't be an issue.

Chris

Chris,

You need a "dotted line" in the sky, or better yet a box. On a road, we use paint to keep cars 3 feet apart and 140 mph head on (70 each direction). We trust that the other guy will stay in his space to avoid collision. Same, I believe, will, in the end, rule airplanes. No FAA needed, except to issue tickets...

My controls for my airplane are the same in the air as on the ground, unlike Terrafugia's controls. The landing gear is much different. Rudder pedals...just don't work well in the transition from flying to driving and conflict with cars.

you are right.. i was thinking (after I wrote this) that we have two examples in movies (Back to the future and Starwars) where there is large amounts of airborne traffic shown. Both have the traffic running in lines. So I envisioned a HUD display of the corridors traffic would flow in.. basically above the existing roadways, but the intersections and cloverleaf/turnpike would all be large cylinders, containing traffic circle/roundabout for flow. everything is controlled, and I can't see any reason why it won't work.

I'm still working on trying to render my ideas, but as soon as I do, I'll present it here.

Chris

Okay.. that took a while... So here are the conceptual renderings. The basic idea is that there is more and smaller airfoils, with more total lift area than a cessna. and the width of the craft does not exceed 100". (height is 96" and length is 240") All yaw and pitch is controlled at the rear, but roll control is by flaps in the centre section on all the angled airfoils. There are twin counterrotating engines.

the wheels are retractable, with a sliding horizontal cover to seal the pontoons. When the wheels are extended, the rear is a combination pair, on a walking beam axle, and the rearmost pair will touchdown first, but the leading edge pair are the road driving wheels. steering wheels are on front. there is also a small pair of water rudders to assist in the water. optionally, there are four hydrofoil ladders (like Alexander Bell's hydrofoil) for higher speed on water, or to assist in water takeoff. (second last image)

remember this is all conceptual.. I'm not an aircraft builder.. just playing.

but if you want to play too, send me your suggestions...

I've only made this in moray/povray, so there are no proper shaping of structural members, radii, etc. I haven't worked out any mechanical linkages etc. who knows if such a thing can be built... the question is, does it resolve any of the issues surrounding a roadable aircraft. I think it does imho.

I did rendered a shot from within the cockpit, and the visibility forward is quite good I think.

Chris

I should add that each airfoil has a 12" chord, so figuring out the lift area is not that hard. I also figured that the twin engine cockpit would carry 2 passengers plus carry on luggage. fuel is in a tank under the seats. I'm not sure how to create a direct mechanic drive to the rear wheels, but maybe its possible to disengage the propellers for road driving, and power the wheels. then when you want to fly or boat, you re-engage the props. maybe if there was drive to the wheels, there could be water propellers too.. just fantasizing.

Chris

Fantasize away Chris! From this sort of thing come workable ideas.

Multiple wings are ineffective which is why biplanes went out in favor of monoplanes. Each wing disturbs the flow fr a long way downstream and above.

You need at least 6x the chord separation between wings.

Good to use the body as part of the lifting surface, reduces drag and increases lift.

Designing the duct entry to your fan can increase velocity over the top surface of the wing, increasing lift.

The conceptual drawings look great!

"Designing the duct entry to your fan can increase velocity over the top surface of the wing, increasing lift"

Can you explain more please? (or draw me a sketch)

thanks,

Chris

Hi chrisg288

Most of the lift from an aerofoil comes from the low pressure region above it.

A wide, narrow inlet over the wing can increase this suction and hence lift.

Of course, if you go too far, the losses in the inlet and other ducting become too high and you lose efficiency. if the duct is too big, the weight penalty can also kill it.

A possibility is to embed smaller, counter rotating fans inside the body, with a porous, low loss, top inlet. Shape the body as the main aerofoil and discharge through the trailing edge of the wing.

Not only does this increase lift, the vectored thrust improves controllability and allows very much increased lift at low speed.

I've been fiddling with the idea for a while now and the numbers look encouraging to enable an air car with vectored thrust giving vertical take off, a fairly low speed transition to conventional lift and quite high cruising speed (about 350 knots remains fairly efficient).

Designing a lifting body which is stable is an interesting task. I think I'm nearly there. A couple of simple gliders will prove it, to be followed eventually by a RC model.

Design would initially be for up to 4 people with a load capacity of about 1 tonne (including weight of passengers). Range about 1000km. Fuel weight becomes excessive beyond this. It may stretch to as much as 2,000 km, but I think that is unlikely in the early stages.

It would be almost essential for the vehicle to be totally automatically controlled - collision avoidance, automatic take off and landing, automatic transition from vertical to conventional flight, automatic selection of route to the destination etc.

Pilot's input would consist of putting in instructions as to destination and then "start".

In areas where traffic is heavy, a computerized traffic system would take full control of all vehicles.

This is all feasible with existing equipment, although some pretty good programming would be needed.

I'll try my hand at getting you some sort of sketch, but I may take the time to learn one of the drawing systems first. I'm a hopeless draftsman.

"Each wing disturbs the flow fr a long way downstream and above."

in a helicopter rotor, is there a loss of lift due to turbulence for the following blade(s)? If you increase the number of blades, does the lift factor decrease? just curious.

Chris

Chris,

A single pusher prop would remove the issue of the props disturbing the air flow over your airfoils. It would also put your engine rearward so your drive selection to the wheels could be simpler. In water, jets would be my suggestion.

Your design appears to be a canard style turned inside out.

Very cool...

Very creative!

btw, what design/drawing tool did you use?

The modeller and rendering engine are freeware.

Moray & Pov-ray

Chris

btw, if you wish to see larger versions, just send me your email addresses. chrisg288@hotmail.com

Nice work Chris

I have never flown an aircraft with engine but only a glider (delta wing). Just looking at the images does not make me feel safe at all. At high speeds yes but when it comes to landing I would want some stability and could imagine this one to be quiet erratic when it comes to side winds at low altitude and slow landing speed. I have seen box kites do strange things and they were at the end of a string.

Long story short: If you were looking for a test pilot I would not apply. If you are looking for admiration of you drafting skills you know were I stand. You are amazing and I hope you take off one day and land safely every time, Ky.

Hi Ky, thanks for the support. You nailed it.. box kite is one part of the inspiration. I put lots of roll control surfaces in, and lots of tail control surfaces too for yaw and pitch, and I figured because its bottom heavy and a longish moment, that it would be stable. there's no telling til a model is built.

cheers

Chris

Hey Chris,

G'Day.

So. Where do ya sit?

How many horsepower do you reckon? (Lift/drag graph would be interesting)

Power to the wheels is very feasible with electrics. ( PEV's, Hybrids, railroad cars, etc.) No losses when the system de-activated.

Just a start.

Cheers,

Stu.

Jeez, I knew I forgot something!

okay my plan was to sit in the 'egg' in the middle. (cockpit) There is windshields on both ends, and would have 2 seats facing forward near the midline of the cockpit. storage behind the seats. Not a big cabin, but enough to get the job done. just think cessna for this part. I think 300 hp would be nice and safe feeling. a pair of 150 hp engines.

Hello Chris.

Great drawing. A couple of half-baked ideas for you to toss around.

For on water propulsion think airboat, seems to work fine in the Everglades.

Hopefully most of your long distance travel would be done in the air, so really all that is needed is an around town vehicle, and not a high-performance road vehicle.

I was thinking a wheel motor combination would eliminate the complexity of linking the engines to the drive wheels. I did a quick search and found a nice unit that Michelin is supposedly going to produce, it weighs about 90 pounds, can sustain 41 hp output continuously, and for short periods can produce 80 hp.

Of course the performance of the vehicle would depend on its weight. And of course weight considerations with the aircraft would demand a light high-performance alternator, or a combination of alternator and light battery packs such as a lithium-ion.

Assuming that the aircraft would weigh somewhere around 2500 pounds, its performance on the ground using this wheel motor should be more than adequate to get you to the hotel, or the restaurant, or home from the local airport, which to me would make a very useful vehicle.

Not sure that it's workable, but I thought I'd throw it out for your conceptual aircraft.

http://www.gizmag.com/michelin-active-wheel-production-electric-car-by-2010/10489/

excellent! thank you. GA

Chris,

Interesting. Will it fly? Control? How would you control it?

Anything will fly with enough power and control. Every seen the "flying lawnmower" (google that quote)?

If you stagger the foils starting with the most forward on top (ladder down going aft), then you can create a lot of lift...serious. I have a program that models multiple foils and it works very well, even better than the best STOL wings. You change the Angle of Attack and you can see the CL just climb... You would need a mechanical way of moving the foils at just the right angles...critical.

The first foil would pitch down, similar to a leading edge flap, the middle foils (depending how many used) are the "wing" as it were, and the last foils are the flaps. If you ladder them down aft, then the flow will be induced to turn down creating lift and remain attached. In essence, that is what every airlines does with one fat middle wing.

In the cruise you make them line up and follow each other. Make the trailing edge somewhat wide and the nose of the following bladed follows in the wake. You can get them close as possible.

A guy actually has a patent on such a ladder wing and has flown it. Can't remember the link.

I looked into Ladder wings. Weight is a big issue.

I use another method to achieve my goals. I see the key issue as static vs dynamic air. The front ladder will see static air, whereas the rear ladder will see dynamic air. This creates a power-pitch relationship that is difficult for humans to fly. Pusher planes land faster than tractors... Look at the STOL contest It all comes down to keeping the flow attached and turning it down.

Helicopters are not viable because they have a relationship of power loss and death. When you take off with power, and that power quits suddenly, the pilot must be able to glide for a safe landing. In a helicopter they need to be moving 60 mph and/or 500 ft to effect an auto-rotation procedure, otherwise you die.

A hybrid hydraulic system could be designed to allow 30 seconds of power if power was lost from mechanical failure or loss of fuel feed. This is where I am going with my system. You want to avoid this area as liability...

The Moller skycar is a perfect example of death by engine failure. What if the fuel is bad, water in the fuel tank, etc...stuff happens. If your car engine failure caused you to die, no car company would be able to produce a car for less than $100-200k.

Seaplaneguy

Dear Seaplaneguy.

I'm very thankful for your input. GA. please see my comments to YWROADRUNNER. If and when I have more updates, I will post here.

Chris

Hello Chris:

I just thought I'd put another two cents worth of thought in it, which brings me up to about four cents which about all my thoughts are worth nowadays.

Skeptic has made some great suggestions i.e. the lifting body (you were previously talking about flying cars in movies, a bad example of the lifting body is the opening scenes from the six million-dollar Man series, bad as it is crashing) ducting the airflow over the wings is also a great idea.

Of course we know it's all hypothetical. I know there is a difference between Reynolds numbers and Reynolds wrap. that's about all I know about airfoil design, however if the ladder wing design is workable it could lead to a much more practical and useful flying car.

So as to my design suggestions. STOL: if ducting the air over the wings emphasizing IF proved to be a workable design, and useful in producing a flying car with STOL characteristics it would go a long in making a flying car practical.

Your twin-engine design with center axis thrusts would be a great safety feature, the center axis thrusts negates the problem associated with engine failures with conventional twin-engine designs (a saying about light Twins is the good engine carries you to the scene of the crash) while having the redundant engine would prevent falling from the sky with a single engine failure.

I would recommend using a fly by wire system, ( a bit of trivia the original space shuttle design utilized five computers each having about 400 K. of memory) a $200 net book would have sufficient computing power for this application. Basically the computer would fly the aircraft, and prevent the driver from doing something stupid, in-flight the inputs would only be telling the computer what you wanted the aircraft to do and the computer would decide how to do it.

The Terrafugia Transition rotates at about 80 miles an hour, I would say there their approach to landing speed would be similar,the 1170 feet required to clear a 50 foot obstacle is also problematic.

In most big cities the little airport is long since gone. And there's no room to build new ones.

Build an flying car that has a 50 mile per hour approach speed or less, and capable of clearing a 50 foot obstacle in 600 feet, with no wings hanging out and you've got a marketable product.

There may not be room to build full-size airports in metropolitan areas, complete with places to park conventional aircraft. However finding places that you could put a strip the width of a 2 Lane Hwy, and 1000 feet long with nothing taller than a 50 foot obstacle around would not be any big problem.

Since you would be driving your car away no need for storage, you could have small strips in convenient locations.

Of course this would not address the other problems brought up in the blog, and it may be impossible to overcome the engineering obstacles, however if you did it would definitely be a useful product, much more practical than other designs.

I figure if you're going to have a fantasy project/thought experiment it might as well be a practical one.

PS: if you do happen to actually succeed in making this product no need to say thanks, just send money.

Also I'm going to be looking into your design software, should it be affordable, which I doubt on my current budget, I will be asking for tips on how to use it .

Thanks YWROADRUNNER,

I'm still in limbo since Seaplaneguy's response (which was awesome) and I'm still trying to reenvision the craft with a forward sloping array of wings.

but to add to the safety features, I've been thinking about parachutes and external airbags (both for this and helicopters. I know patents have been filed for helicopters)

I do think the fixed wing and dual engine plan offer safety, plus the fact that you can actually pack more square footage of airfoil into this kind of shape than a conventional aircraft, once you assume or prove that the system of airfols will work (thank you seaplaneguy)

I think that some of the airfoils will have to rotate horizontally, as noted by seaplane guy. What he has suggested, which I did not think of, was to have them rotate independently to produce a larger lift effect. but all in all, it increases the safety factor.

As for take-off space, I was thinking that if the wings were basically fixed, then they would have to be set at an AOA such that they wouldn't lift the vehicle off until a minimum velocity was acheived, such as 140 kmh.. but you know that probably is a bad idea. I think that rotating airfoils will be a requirement, so they can be oriented to produce zero, or downward force for road travel. (and parking in windy areas) I do think that areas could be designated on highways and other areas, plus more access to waterways (cheapest runways) or just put water based runways on the sides of the roads/ditches

another safety feature is the spars that are angled on the leading edges, which don't really need to be there, but if you are flying in locations with lots of hydrolines, they could be lifesaving... currently the front prop would also contact the lines, but that could be modified to be cleared.

moray/povray is much easier to learn than 3DS or other.. but a grounding in cad is very helpful to think in those kinds for coordinate systems. I was lucky when I got started, I found a book with a disk in it, back in the early 90's.

there are good tutorials on the moray site. but you should download the moray program from the povray site. (since they (povray) have taken ownership of moray, they have made it freeware. the one from the moray site is still shareware.)

Chris

Hello ozzb

I went to their site last night and read the literature, I don't think they're really intending to land on roads, but rather the same place as conventional aircraft land, airports, private landing strips, etc. the performance of the aircraft would not make it well suited for anyplace with obstacles.

Your two posts bring up an interesting point, I don't think the numbers would be anywhere near as high as your thinking, but I believe the prospective buyers would be a problem.

The Beechcraft V45 bonanzas has a well earned reputation of doctor killers, not because it's a bad aircraft but because low time pilots that could afford the aircraft i.e. doctors and lawyers and such would go out and buy one and were ill-prepared to operate a complex high-performance aircraft that was slightly temperamental.

With the new sport pilot category you can be called a pilot in 20 hours, I'm sure a lot of fairly well-to-do professionals would run out and buy one of of the aircraft if it ever goes into production.

I'm not sure you would see drunks falling from the air but certainly doctors and lawyers, I hope if the the aircraft is ever certified the aircraft parachute is mandatory I would rather have one parachuting into my house, then flying into it.

A beautiful concept, I hope this one works. As far as flying into telephone poles and wires I think the general idea is landed at an airport, and drive where you want to go.

Although I'm sure many have, personally I never found any way I could legitimate a light plane as anything more than a fun hobby. Something I could have driven from the airport once I got there could have been very useful when I was flying.

As previously mentioned insurance would be a bear, and a unnoticed fender bender could be fatal.

However I am sold, all I need to do is win the lottery, and get my medical back and I'll buy one.

Drunks in the sky do we really need them dropping in on us?

The FAA really will have the hands full with this one.

Must be funded by one the oil company all the research for fuel efficient cars. It will need to burn more fuel to lift the weight of the vehicle off the ground.

And its not the first.

I do not believe that the FAA will ever allow this project to get off the ground.

If people have problem controlling a car on 2 dimensional street, how can they control a plane?

I guess most of them will die in first year and by natural selection we'll only have the best.

You have to be a pilot first off which eliminates the general public. If you can afford to be a pilot, which I am, you can probably afford an ultralight or a helicopter. There will always be someone as a market for something like this, but a helicopter is a much better solution. I saw this unit at Oshkosh, and watched the wing folding actuation in person. I think it is 'cute', but for real pilots, it is of limited versatility. I don't know who started the 'plane in every garage' but it is unlikely to ever happen.

Here is a very valid flying vehicle.. and fun!