Lear Fan 2000

[Leo]

Re: Lear Fan 2000

That was the coldest and wettest year I remember, except the beginning of the week in 85 and the nights in 89.
But the weather in 82 gave some awesome sights in the evenings when the racers went up to play. I can still remember the Super Corsair winding up one evening with that rumble echoing off the clouds.

Leo

[Unregistered]

Re: Lear Fan 2000

N21LF was in Oshkosh. It is now being resored for static display in Dallas, Texas, the Frontiers of Flight Museum, opening 6/2003. I'm on the connservation team. A real pain to reconstruct an aircraft that was a prototype and never was intended to be disassembled. To keep track, try www.flightmuseum.com.

[Unregistered]

Re: Lear Fan 2000

Hi Guys,

Just stumbled across this thread after searching for some info on the ill-fated Lear Fan project. The Lear Fan was Bill Lear's last project before his death and it's true that only 3 prototypes were completed. They all still exist in places in the US as has been mentioned already on the thread. The Lear Fan was to have a large portion of it's funding from the British taxpayer and a fabrication and assembly plant created in Northern Ireland where great unemployment and political instability resided. Unfortunately the funding did not quite stretch to getting the Lear Fan through certification and no more funding was forthcoming from the British Government. With Bill Lear not around to drive the project it failed. It was one of if not the first civil aircraft to use almost exclusively carbon fibre and kevlar in it's production and many of the developments on the Lear Fan drove sucessive and future aircraft developments of today, particularly in the fabrication and use of composites in aircraft production.

It was a very pretty aircraft, one of my all time favourites and sits alongside the Gates Piaggio Avanti in my dream hangar.

Wishing you blue skies,

Rupert C Kent - UK

[Unregistered]

Re: Lear Fan 2000

The use of composites is one of tha main resons it failed. By the time they made it stong enough to meet the FAA's liking it was way to heavy and made it somewhat of a dog. One of many examples of why METAL is the way to go.

[Randy Haskin]

Re: Lear Fan 2000

The use of composites is one of tha main resons it failed. By the time they made it stong enough to meet the FAA's liking it was way to heavy and made it somewhat of a dog. One of many examples of why METAL is the way to go.

Metal is the "way to go" if you build airplanes with the materials and methodology like they were applied on aircraft built this way 20 years ago. The structures and materials technologies are significantly better now than they ever have been.

[Peashooter]

Re: Lear Fan 2000

The use of composites is one of tha main resons it failed. By the time they made it stong enough to meet the FAA's liking it was way to heavy and made it somewhat of a dog. One of many examples of why METAL is the way to go.

My composite Long EZ has an empty weight of 850 lbs, equipped for night IFR. Its load limits are +/- 12 Gs. (Static tested by Burt Rutan.) It cruises at 190 mph on 130 hp and 7 gph with 52 gal capacity. Name a production spam can that can match those numbers. I like metal too, just don't under estimate composites. Peas

[Randy Haskin]

Re: Lear Fan 2000

Is fibreglass-over-foam really considered "composite" material in the current use of the word?

[Peashooter]

Re: Lear Fan 2000

Randy: Not in the strictest terms, although the EZ does use a mix of E & S glass and a little kevlar here and there. The Berkut (a hot Long EZ) is composite; glass, carbon & kevlar in an optimised layup schedule. Peas

[speeddemon]

Re: Lear Fan 2000

The use of composites is one of tha main resons it failed. By the time they made it stong enough to meet the FAA's liking it was way to heavy and made it somewhat of a dog. One of many examples of why METAL is the way to go.

Spoken, perhaps, as one who doesn't know how to 'really' build true composite parts. As one who not only knows, but 'does', I can say that I'll take a composite part over metal for just about any vehicle...short of a tank or an attack aircraft.

Just my .02, though.

Speeddemon

[Unregistered]

Re: Lear Fan 2000

When a metal part fails, it fails on the outside where you can see it on composite parts start to fail on the inside where you can't see it. Another con of composites is if you drop a tool on a wing or fuse your going to have a lot more of a problem than if it was metal. There is also the problem of delamination. This was one of the downfalls of the starship and also has become a problem on the C-130J props, they start to delaminate when flying in the rain. The long e-z is probably rutans most succesful design but look at the Pond racer and Rutan AMSOil racer. The AMSoil wing was supposed to flex as it banked and change the angle of attack and reduce drag making it hold its speed around the turns, but in reality it slowed it down in the turns and eventualy caused a high speed stall destroying the plane and luckily Dan was unhurt. Another example was voodoo's composite cowl, high temps from the exhaust started burning it up, although it seems they have fixed the problem. Composites do have a place in aviation but I am very scepticle about entire planes being constructed from them. I wouldn't trust any strucual part made from composites but that is just me.

[First time Juke]

Re: Lear Fan 2000

My composite Long EZ has an empty weight of 850 lbs, equipped for night IFR. Its load limits are +/- 12 Gs. (Static tested by Burt Rutan.) It cruises at 190 mph on 130 hp and 7 gph with 52 gal capacity. Name a production spam can that can match those numbers. I like metal too, just don't under estimate composites. Peas

I saw similar to that EZ plane flying over my residence a month ago and judging by the sound of the engine that plane was doing a lot faster than a normal Cessna or a Piper at the same engine settings..it was a jet like speed..well sorta kinda.

Peashooter has a point here.

My racer layout below ( inspired by the Dart and Lear Fan 2000 dsigns ).

[King]

Re: Lear Fan 2000

When a metal part fails, it fails on the outside where you can see it on composite parts start to fail on the inside where you can't see it. Another con of composites is if you drop a tool on a wing or fuse your going to have a lot more of a problem than if it was metal. There is also the problem of delamination. This was one of the downfalls of the starship and also has become a problem on the C-130J props, they start to delaminate when flying in the rain. The long e-z is probably rutans most succesful design but look at the Pond racer and Rutan AMSOil racer. The AMSoil wing was supposed to flex as it banked and change the angle of attack and reduce drag making it hold its speed around the turns, but in reality it slowed it down in the turns and eventualy caused a high speed stall destroying the plane and luckily Dan was unhurt. Another example was voodoo's composite cowl, high temps from the exhaust started burning it up, although it seems they have fixed the problem. Composites do have a place in aviation but I am very scepticle about entire planes being constructed from them. I wouldn't trust any strucual part made from composites but that is just me.

Obviously you live in the past.

I work with primarily metal structures. I design major structural repairs for aircraft, mostly the Cessna Citation business jets.

We also do many repairs in the structural composites area. Used to do alot of sailplanes and now mostly composite structures on the jets. The composite repair is very easy (using the correct materials) to perform and your average laymen can perform an adequate approvable repair and I feel a better repair than most people can do to aluminum.

Some of the things I have seen people do with aluminum are just plain scary structural wise.

I can't quite figure out why you say you cannot see the damage on composites. Can you explain that? And why do you think aluminum fails only on the outside and not the inside. Did you see the many tapes from last year on the fire bombers?

[Randy Haskin]

Re: Lear Fan 2000

When a metal part fails, it fails on the outside where you can see it

Obviously you've never been to an NDI shop before.

[Peashooter]

Re: Lear Fan 2000

Obviously you've never been to an NDI shop before.

NDI? Explain, please. Peas

[Randy Haskin]

Re: Lear Fan 2000

NDI means Non-Destructive Inspection. In the Air Force this is a group of specialists who look for metal fatigue using, among other things, an x-ray process used to detect metal failures -- cracks and such beneath the surface that aren't visible during a normal inspection process or by using dye penetrant.

My point was that, if the anonymous poster's assertion that "When a metal part fails, it fails on the outside where you can see it", then there would not be a need for such a shop.

Since the Air Force (and I imagine the rest of the aviation industry) spends lots of $$ on such men and equipment, my guess is that the anonymous poster is incorrect in his statement.