roadable Terrafugia nears test launching

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Dave Krall CFII

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Dave Krall CFII SEL SES, Cmcl HELI
A roadable aircraft slated to meet LSA requirements. Static load testing of the strutless, folding wing flying car appears successful. See PIX in newsletter archieves which do NOT require a subscription: http://www.terrafugia.com/
 
I think it will be difficult for an aircraft that technically can be driven on a road to comply with both the LSA requirements and the highway safety requirements of USDOT (and its equivalents in other countries). Mandatory features like air bags and other crash safety requirements for automobiles add weight, which I can't help but think would put the vehicle over the weight limit for LSA. Then again, I'm not engineer (nor do I play one on television), so my hunch is nothing more than that.

I guess it might be possible to register the vehicle as a "limited-use automobile," however, which would exempt it from certain requirements, but also would restrict it from major highways. That might be handy in some places, provided the vehicle performed acceptably both in the air and on the ground -- which would be quite a trick to pull off.

Others have tried to develop airplane / automobile combinations, sometimes with tragic results.

http://en.wikipedia.org/wiki/Aerobile

-Rich
 
I can hardly believe they got a strutless double folding wing and roadability within LSA weight limits.

They are applying for exemptions regarding airbags and emissions. The highway is about the last place to take that rig...
 
I'll save my deposit until I see it rotate and flare. The other point of true stupidity is making it four wheeled and having to meet federal standards as an automobile, rather than 3 wheeled to certify as a motorcycle. This thing is so full of design errors its comical.
 
Not an engineer, but I'm still trying to figure out how 100 hp = 100 kts cruise on 4.5 gph in such a wide looking cabin.

Heck, a Beech Skipper with with 110 hp (?) struggles to beat 90 kts in the real world.
 
Pi1otguy said:
Not an engineer, but I'm still trying to figure out how 100 hp = 100 kts cruise on 4.5 gph in such a wide looking cabin.

Heck, a Beech Skipper with with 110 hp (?) struggles to beat 90 kts in the real world.
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There's so many design errors with that thing.... another project out there by college kids without any real experience.
 
Henning said:
I'll save my deposit until I see it rotate and flare. The other point of true stupidity is making it four wheeled and having to meet federal standards as an automobile, rather than 3 wheeled to certify as a motorcycle. This thing is so full of design errors its comical.
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Although 3 wheel motorcycle cert would be nice, I'm thinking they went with 4 four wheels due to the high lateral mass from the wings and the highly desirable side by side seating.

I'm curious what other design flaws are apparent.
 
wabower said:
Didn't they neglect/forget to re-attach the lift struts?
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One report mentions bad welds...

I don't know how many flights it actually made but the Mizar's concepts weren't too bad. If they were combined with todays composite construction, weight would go down considerably making it much more feasible.
 
Dave Krall CFII said:
Although 3 wheel motorcycle cert would be nice, I'm thinking they went with 4 four wheels due to the high lateral mass from the wings and the highly desirable side by side seating.

I'm curious what other design flaws are apparent.
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Look where the rear wheels are, what do you think rotational speed will have to be? How hard do you think the front end is going to slam down on landing? How the hell are they going to make that wing strong enough while keeping the whole package under 1320lbs? Besides, there's no reason a three wheeler wouldn't work with side by side seating. It a school project fund raiser is all it is, and it isn't really paying off, because the people who would give them money aren't because they also see the obvious problems. It was built in order to take the CAFE foundation prize which never materialized. They were banking on the MIT name winning them the prize, but it's an emu, ugly, poorly designed, and won't fly. It'll fly like a turkey at best.
 
Henning said:
Look where the rear wheels are, what do you think rotational speed will have to be? How hard do you think the front end is going to slam down on landing? How the hell are they going to make that wing strong enough while keeping the whole package under 1320lbs? Besides, there's no reason a three wheeler wouldn't work with side by side seating. It a school project fund raiser is all it is, and it isn't really paying off, because the people who would give them money aren't because they also see the obvious problems. It was built in order to take the CAFE foundation prize which never materialized. They were banking on the MIT name winning them the prize, but it's an emu, ugly, poorly designed, and won't fly. It'll fly like a turkey at best.
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So you think I should ask for my money back?
 
RJM62 said:
I think it will be difficult for an aircraft that technically can be driven on a road to comply with both the LSA requirements and the highway safety requirements of USDOT (and its equivalents in other countries). Mandatory features like air bags and other crash safety requirements for automobiles add weight, which I can't help but think would put the vehicle over the weight limit for LSA...
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Consider that even Bentley has to give three copies to the NHTSA so they can crash it into a concrete wall. :yikes:

There has to be a reason they insist on calling it a roadable aircraft, as in they don't intend to try for highway certification.
 
Henning said:
Look where the rear wheels are, what do you think rotational speed will have to be? How hard do you think the front end is going to slam down on landing? How the hell are they going to make that wing strong enough while keeping the whole package under 1320lbs? Besides, there's no reason a three wheeler wouldn't work with side by side seating. It a school project fund raiser is all it is, and it isn't really paying off, because the people who would give them money aren't because they also see the obvious problems. It was built in order to take the CAFE foundation prize which never materialized. They were banking on the MIT name winning them the prize, but it's an emu, ugly, poorly designed, and won't fly. It'll fly like a turkey at best.
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I saw a PIX in their newsletter archieves of sand bag loading and seem to recall that the stress testing of the wing has passed.

Roadables are in a very unique niche and most designs are quite "ugly", especially to most regular pilots that does not want their mission profile. If it does indeed fly like a turkey that would be OK, as long as it's at least a wild turkey which flys quite well!

As a pusher prop, the CG looks rotatable if the canard is big enough, even if it may be somewhat nose heavy when fully loaded. Should be an interesting first flight video if nothing else.
 
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As ugly as it is, look at the bright side- if the cops are chasing you all you have to do is extend the wings.
 
I'm actually looking forward to watching this fold out.... as an engineering who has work in auto and aviation they face a lot of challenges. The lady I sopke to at Osh was very well versed in both. I do know they are working to get varances from DOT regeulations like side mirrors, they are looking to put in cameras and video screans instead because of the added drag. I even asked if they plan to crash test it as a car, the answer was a yes. Wouldn't you just hate to see it crashed tho..
 
From the video: "weighs under 890 pounds empty"...wow. That's a useful load of just 430 pounds. They're doing good to get that low, but still...
 
Hmmm... since it's an LSA, and thus prohibited for use "in futherance of a business," the market will be pretty small.

But, watching those wings fold down (into failure direction)....yikes!
 
dmccormack said:
Hmmm... since it's an LSA, and thus prohibited for use "in futherance of a business," the market will be pretty small.
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Not quite. The limitation is on a sport pilot, or another pilot operating under the sport pilot rule without a medical, not on the aircraft itself. See 61.315(c)(3). A private pilot or higher can use it as he would any other airplane, subject to the limitations in the POH.
 
jmaynard said:
Not quite. The limitation is on a sport pilot, or another pilot operating under the sport pilot rule without a medical, not on the aircraft itself. See 61.315(c)(3). A private pilot or higher can use it as he would any other airplane, subject to the limitations in the POH.
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Good point -- the video narration touted the a/c as an LSA and thus required "less training."

But the limitation is on the pilot, not the aircraft.
 
This is a wonderful science project, but a horrible business venture.

The requirements for a safe aircraft and automobile are too divergent to come up with a vehicle that satisfies both in an effective manner. At least until a better powerplant is invented.

There was another project that took more of a motorcycle with wings approach. It has a much better chance to be successful.


Dave Krall CFII said:
A roadable aircraft slated to meet LSA requirements. Static load testing of the strutless, folding wing flying car appears successful. See PIX in newsletter archieves which do NOT require a subscription: http://www.terrafugia.com/
Click to expand...
 
jmaynard said:
From the video: "weighs under 890 pounds empty"...wow. That's a useful load of just 430 pounds. They're doing good to get that low, but still...
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Sure. Two standard 180 lb adults and 30 lbs of baggage and charts leaves a whopping 40 lbs for fuel. That's about an hours worth so given that I always want an hour's fuel in reserve, the range is about 500 ft.

I'm also thinking that with the rear wheels so close to the elevator, pitch control at rotation might be more difficult than one would like. And how in the world could such a vehicle meet the crashworthiness requirements?
 
gismo said:
And how in the world could such a vehicle meet the crashworthiness requirements?
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My guess is that they're depending on the advanced materials to solve this problem. Still, it'll be interesting to see just what one of those does in a crash test. For that matter, just how many vehicles will they need to crash-test before being able to sell them? A car maker can write off a handful of them, but for an aircraft maker, that's rather a different thing.
 
When I was speaking to one the the employees at Osh, They have been working with DOT to see if they can get a waiver on some things as it is a roadable aircraft, not a car. (The reason the motorcycle idea works better is that there are not as many requirments on motorcycles as there are cars) One thing they were working on was a variance to side view mirrors. Allowing them to use a camera system as the mirrors create too much drag and with the wings folded dont do much good anyway.

I wasn't much impressed with the power plant they choise... but their reasons for chosing it were sound. I really think they have the best bet out there for getting it off the ground.

I'm watching with excitment.

Missa
 
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Missa said:
(The reason the motorcycle idea works better is that there are not as many requirments on motorcycles as there are cars)
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...but you gotta do a wheelie evey takeoff and every landing....

8501.jpg
 
one txt messaging 16 year old with a car full of friends smacking into the back of that thing at a stop light would be the end of it.
 
etsisk said:
one txt messaging 16 year old with a car full of friends smacking into the back of that thing at a stop light would be the end of it.
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Yep... one thing you would have to do is have good insurance!
 
gismo said:
Sure. Two standard 180 lb adults and 30 lbs of baggage and charts leaves a whopping 40 lbs for fuel. That's about an hours worth so given that I always want an hour's fuel in reserve, the range is about 500 ft.

I'm also thinking that with the rear wheels so close to the elevator, pitch control at rotation might be more difficult than one would like. And how in the world could such a vehicle meet the crashworthiness requirements?
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The long lever arm of lift from the canard seems to more than make up for any of those pitchability concerns, as shown when it snaps up off the runway to takeoff. The gross weight can be bumped up when in the experimental category assuming it has the load limits to take it, which most LSAs do. Then it becomes utilitarian for the creative, adventurous, and nicely heeled business people out there.

The fact that a viable roadable aircraft drives and flys at all deserves congratulations. Expecting much more than "sport" capabilities from a roadable aircraft at LSA weights is not feasable at this time. Nor are the safety protections we have come to enjoy in our typical cars and aircraft. It is a compromise situation necessary at this time to achieve higher, broader goals.
 
Which Lycoming/Continental or other engine, would be the best candidate to replace its Rotax with?

Missa said:
When I was speaking to one the the employees at Osh, They have been working with DOT to see if they can get a waiver on some things as it is a roadable aircraft, not a car. (The reason the motorcycle idea works better is that there are not as many requirments on motorcycles as there are cars) One thing they were working on was a variance to side view mirrors. Allowing them to use a camera system as the mirrors create too much drag and with the wings folded dont do much good anyway.

I wasn't much impressed with the power plant they choise... but their reasons for chosing it were sound. I really think they have the best bet out there for getting it off the ground.

I'm watching with excitment.

Missa
Click to expand...
 
Missa said:
When I was speaking to one the the employees at Osh, They have been working with DOT to see if they can get a waiver on some things as it is a roadable aircraft, not a car. (The reason the motorcycle idea works better is that there are not as many requirments on motorcycles as there are cars) One thing they were working on was a variance to side view mirrors. Allowing them to use a camera system as the mirrors create too much drag and with the wings folded dont do much good anyway.

I wasn't much impressed with the power plant they choise... but their reasons for chosing it were sound. I really think they have the best bet out there for getting it off the ground.

I'm watching with excitment.

Missa
Click to expand...

Dave Krall CFII said:
Which Lycoming/Continental or other engine, would be the best candidate to replace its Rotax with?
Click to expand...

See emphasis.
 
I agree with others I would have went with 3 wheels not 4. Not sure how they will get it approved for the road.
Also I cant imagine what insurance would cost. Even a small accident and you just totaled your $200,000 car/plane. What insurance do I need Car or plane or both.
Plus it is an ugly car and just as ugly of a plane.

All that said I think they are doing a great job and I hope the best for them.
 
I wonder if it's flying street legal golf cart can you get around some DOT regulations.

Does not do anytjing for insurance though.
 
RMCN172RG said:
I wonder if it's flying street legal golf cart can you get around some DOT regulations.

Does not do anytjing for insurance though.
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I think the problem with being a street legal golf cart is that you can only go on negiborhood roads, not e-ways. Part of the advertised utility is that instead of cancling your VFR cross country flight, you can fly twoard the weather, land at an airport, drive under the weather, go to next VFR airport and take off agian.
 
Missa said:
I think the problem with being a street legal golf cart is that you can only go on negiborhood roads, not e-ways. Part of the advertised utility is that instead of cancling your VFR cross country flight, you can fly twoard the weather, land at an airport, drive under the weather, go to next VFR airport and take off agian.
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Marketing versus reality.

If you could fly into an airport commute 10 miles home and park it in the garage it would be fine.

Can you imagine passing a truck at 70+ mph in a so MPH crosswind with the wings folded.:eek:
 
RMCN172RG said:
Marketing versus reality.

If you could fly into an airport commute 10 miles home and park it in the garage it would be fine.

Can you imagine passing a truck at 70+ mph in a so MPH crosswind with the wings folded.:eek:
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It's no greater a cross section then your standard SUV... bit lighter tho. Still controllable if you are a decent driver. - Then again most people had trouble with a tire blowing out... hopefull "most people" will not be driving this.
 
Missa said:
Then again most people had trouble with a tire blowing out... hopefull "most people" will not be driving this.
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My greatest fear while riding a motorcyle on the highways is a tractor-trailer tire blowout as I am passing it.

The occupants of this vehicle won't fare much better when a 60 lb chunk of rubber comes hurling through the air at 80 MPH into that fine, lightweight fuselage....
 
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