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LEBillfish
05-31-2005, 02:22 PM
http://www.geocities.com/CapeCanaveral/Hangar/8217/fgun/fm1-b.jpg

Left, the Bell FM-1 Airacuda was designed around two 37mm M4 cannon in the engine nacelles and their gunnery control system. [26]

The most famous example of such a fighter is the Bell FM-1 Airacuda, a twin-engined aircraft first flown in 1937. The FM-1 was a low-wing monoplane with pusher propellers, driven by turbosupercharged Allison V-1710 engines. This arrangement left room for a 37mm M4 cannon in the nose of each engine nacelle, hydraulically controlled, with a coaxial machinegun to assist in aiming. A gunner in the nose of the FM-1 used a Sperry autopilot, a fire control system originally developed for anti-aircraft cannon, and an optical sight to aim these weapons. Impressive it was, but nobody could find a real need for it, or invent the tactics for its use; and the FM-1 faded into obscurity.

http://www.geocities.com/CapeCanaveral/Hangar/8217/fgun/fgun-bi.html

LEBillfish
05-31-2005, 02:22 PM
http://www.geocities.com/CapeCanaveral/Hangar/8217/fgun/fm1-b.jpg

Left, the Bell FM-1 Airacuda was designed around two 37mm M4 cannon in the engine nacelles and their gunnery control system. [26]

The most famous example of such a fighter is the Bell FM-1 Airacuda, a twin-engined aircraft first flown in 1937. The FM-1 was a low-wing monoplane with pusher propellers, driven by turbosupercharged Allison V-1710 engines. This arrangement left room for a 37mm M4 cannon in the nose of each engine nacelle, hydraulically controlled, with a coaxial machinegun to assist in aiming. A gunner in the nose of the FM-1 used a Sperry autopilot, a fire control system originally developed for anti-aircraft cannon, and an optical sight to aim these weapons. Impressive it was, but nobody could find a real need for it, or invent the tactics for its use; and the FM-1 faded into obscurity.

http://www.geocities.com/CapeCanaveral/Hangar/8217/fgun/fgun-bi.html

GuNzABlaZiN
05-31-2005, 02:53 PM
Interesting, but will it be in 4.0? http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

vocatx
05-31-2005, 07:56 PM
I've never seen that particular photo of the Airacuda before, and I've got several. I guess I'm in a minority, but that airplane has always struck me as a "sexy" looking one. The nine YFM-1 had teh taildragger configuration while the three YFM-1A had tricycle gear.

Thanks for the great pic, Billfish.

Frequent_Flyer
05-31-2005, 08:57 PM
I smell a modeling project for LeBillfish. Looks like the FM would be similar to that twin 109 thingy, only better looking. You got a week, put the coffee on.

woofiedog
06-01-2005, 02:53 AM
A little info and story written by From Eric Shilling of the American Volunteer Group (Flying Tigers} About flying the YFM-1.

http://sbiii.com/avpix/boyncuda.jpg

Subject: Bell Airacuda (YFM-1) Date: 24 Jul 1996 19:09:25 GMT

"Another airplane I flew was the YFM-1 Airacuda, made by Bell Aircraft Corporation in Buffalo, New York. It was a pusher built around two exhaustdriven turbo-charged Allison engines of 1040 horsepower each. It was new in type and concept. The design's hypothesis was that it would be used as a bomber-destroyer. It had two thirty-seven millimeter cannons, one in the nose of each nacelle, but little in the way of defensive weapons. Several other innovations were being explored on the Airacuda that were not used on any previous military airplanes. Because some of the innovations were impractical, they haven't been used since.

Flying the Bell Airacuda was a new experience for me, since it was the first pusher aircraft I'd ever flown. Its handling characteristics were foreign to anything I had ever had my hands on. Under power it was unstable in pitch, but stable with power off. While flying straight and level, if a correction in pitch was required, a forward push on the control resulted in the airplane wanting to pitch over even more. Pitch control became a matter of continually jockeying the controls, however slightly, even when the aircraft was in proper trim. The same applied if pulling back on the control. It would tend to continue pitching up, requiring an immediate corrective response. The same happened in a turn. With power off, the Bell became stable in pitch. This was fortunate because during approach and landing, it was very stable, and a nice flying airplane.

It was built around several new ideas never tried before, and was unlike any other fighters up to that time. First, it wasn't designed to be a fighter plane, although many had the mistaken idea that it was. It could be better described as a bomber destroyer. The tactics suggested by its designer were based upon the machine being used as a flying antiaircraft platform. It was a defensive weapon to be used only against incoming bombers that were beyond the range of escorting fighters. Although it had some defensive weapons, I think they were more psychological in nature, for the benefit of the YFM-1 crew, than practical.

The tactics envisioned were that the Airacuda would fly in trail, just out of range of the enemy bomber formation's guns. Up to that time bombers had 30 and 50 caliber weapons. It is important for the reader to keep in mind that the Bell would be used only against enemy bomber formations that were out of range of protective fighter escort. The YFM-1 had little or no effective firepower for its defense, and as a consequence, would be a sitting duck against agile fighters. The front of each engine nacelle housed a 37 mm, gyro-stabilized cannon. With the longer range of the 37 mm guns, they could pluck the enemy bombers off, one by one. In other words, it was a mobile antiaircraft gun platform.

The primary function of the men in the nacelles was loading the guns, although they could be fired by the gun crew in an emergency. Initially, the pilot of the plane aimed the airplane in the general direction of the formation. Further correction in aim would then be made by the gun control officer, and fired by him. His station was directly behind the pilot, using an inverted periscope that came out through the belly of the ship to aim the guns. The fire control officer would clutch the guns into the gyros, which stabilized them. From that moment on they would stay on target. The person operating the guns could then make any further correction and fire away until the bomber was brought down. His position had swingout flight controls, and in an emergency he could fly the airplane. If it was necessary to abandon the aircraft, the pilot would have to feather both engines to prevent the propellers from chewing the men to pieces, especially those in the nacelles. The flight manual said they would feather in six seconds; that's a long time in my book.

In addition to being a pusher airplane, the YFM-1 also had other unusual features. It had only one engine-driven accessory, an emergency fifty-ampere generator on the left engine. The Bell Airacuda was an electrical nightmare. All normally driven engine accessories, such as fuel pumps, hydraulic pumps, vacuum pump, and the gyros stabilizing the guns were electrically driven. Because of all the electrical energy required, the ship had to have a full-time auxiliary power unit. The auxiliary power unit was driven by a powerful four-cylinder gasoline engine which ran all the equipment. Since the aircraft was required to operate at high altitudes, the APU also had to be turbo-supercharged. To do this, a dual bleed came from the same exhaust turbo-chargers that super-charged the Allison engines. The power unit was the weak link in the system.

Changing fuel tanks was simple. There was no fuel selector as we normally think of one. Each fuel tank had its own fuel pump. Tanks were changed by flipping the switch on for the electric fuel pump of the desired tank. The gear and flap selector was similar in appearance to the C-47's fuel selector. Gear and flaps were activated by rotating this control to the appropriate position. It only had three positions--takeoff, fly and land--and could be turned only in a clockwise direction. In the takeoff position, the flaps were retracted. In the fly position, the gear was retracted, and in the land position, both gear and flaps came down. The flaps immediately followed the gear. Unfortunately the two were not isolated from each other, and that posed a minor problem.

To get gear only, such as on downwind, the pilot would watch the gear as it extended. When almost all the way down, he tripped the circuit breaker. Then on final, when the flaps were required, the breaker was turned back on. At the completion of the landing roll, the pilot would select fly position, retracting the flaps.

The engines had no cooling fans, so in summer the airplanes had to be towed to the takeoff position before starting. As soon as there was an indication of an oil temperature rise, the pilot immediately started the takeoff run. When landing, if the oil temperature was on the high side, the pilot would have to shut the engines down and have the ship towed to the parking area. If the airplane had only a short distance to taxi, it could continue to its parking place under its own power.

One recurring problem experienced by pilots flying the Airacudas was that the auxiliary power unit would all too frequently stall or quit. The reverse current relay would stick and motorized the generator. Since this would drain most of the current from the battery, all electrical systems became inoperative: NO fuel pressure, NO vacuum, NO hydraulic pressure, NO gear, NO flaps and NO ENGINES. The first time I lost both engines, I was in the landing pattern on base leg just about to turn final when the APU quit, then a second later so did both Allison engines.

Fortunately, it occurred right after the gear locked down, and I was able to make the runway without power. Although the airplane had a wobble pump, the handle was only four inches long. It was impossible to supply two Allison engines with the wobble pump, since they consumed over three hundred gallons of fuel per hour at full power. Its only purpose was to start the engines.

The second time the problem occurred, I was flying on instruments, but again I was fortunate. They both quit not too long after I had started into the overcast. I knew there was a couple thousand foot ceiling under the cloud base, so I dove out of the cloud before the gyros tumbled. All the while, the crew chief was trying to restart the APU, which started with room to spare. With the APU going, the fuel pumps came on and both Allison engines began producing power. The remainder of the trip to Langley was uneventful and I made a safe landing there."

Erik Shilling was a Flight Leader in the 3rd Squadron, AVG (Flying Tigers), and is the author of "Destiny: A Flying Tiger's Rendezvous with Fate".

Art-J
06-01-2005, 05:24 AM
Great story. I knew this plane was a wicked crate, but I didn't know it was THAT wicked! Maybe it's good that this plane never went into production... If Young unexperienced pilots at the beginning of the war had problems with flying sophisticated B-26 for example, I don't want to think what nightmare it would have been for them to fly this bird!

Platypus_1.JaVA
06-01-2005, 01:55 PM
Maybe the American aproach to the "zerst├┬Ârer" concept.

Nice aircraft.

VonKlugermon
06-01-2005, 02:08 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Art-J:
Great story. I knew this plane was a wicked crate, but I didn't know it was THAT wicked! Maybe it's good that this plane never went into production... If Young unexperienced pilots at the beginning of the war had problems with flying sophisticated B-26 for example, I don't want to think what nightmare it would have been for them to fly this bird! </div></BLOCKQUOTE>

Aircuda's wild alright, but speaking of the B26:
http://img.photobucket.com/albums/1003/willson/xb26h-1.jpg

http://img.photobucket.com/albums/1003/willson/xb26h-0.jpg

Look ma, I'm a B-52! (Sort of!)

Willy