Airborne Awesomosity, Military-Grade Awesome

Point Defense – When All Else Fails Be Really Different

Focke Wulf Triebfluegel

 

Desperation can lead to creativity. When you have nothing else to lose you will look into every option possible. This led to one of the more interesting designs in the wars waning days with that in mind we look at our next point defense aircraft.

 

 

Focke Wulf Triebfluegel

 

 

The point defense role became more important as the war started to wind down with the American bombers destroying anything related to the war machine. From this comes one of the more original ideas to come out of the aviation design studios.

With the jet and rocket engines making inroads there really wasn’t any option that was ignored. The ramjet offered many advantages in the second half of the war. It was extremely simple to build and didn’t require much in the way of rare metals.  It also offered performance on par or better than the current generation of jets. There were two downsides. One was that it used a very large amount of fuel which was in short supply. The ramjet is a simple conical show that compresses the air without the use of compressers. This required the engine to be moving at a pretty good rate of speed before it will work. To get around this this aircraft would have solid rockets on the propelled tips to get enough speed and airflow to work.

 

[youtube]http://www.youtube.com/watch?v=bqqQ48KFXJE[/youtube]

 

General characteristics

  • Crew: 1
  • Length: 30 ft (9.1 m)
  • Wingspan: 38 ft (12 m)
  • Gross weight: 5,200 lb (2,359 kg)
  • Powerplant: 3 × Pabst ramjets, 2,000 lbf (8.9 kN) thrust each
  • Powerplant: 3 × Walter liquid fuel rockets
  • Powerplant: 2 × standard German Walter 109-501 RATO units , 3,306 lbf (14.71 kN) thrust each

Performance

  • Maximum speed: 621 mph (999 km/h; 540 kn)
  • Never exceed speed: 1,730 mph (1,503 kn; 2,784 km/h)
  • Minimum control speed: 150 mph (130 kn; 241 km/h)
  • Service ceiling: 50,000 ft (15,240 m)
  • Rate of climb: 160 ft/min (0.81 m/s)

Armament

  • Guns: 2 × 30 mm MK-103 each with 100 rounds + 2 × 20 mm MG-151 each with 250 rounds

Focke Wulf Triebfluegel Cutaway

Had they attempted to build a prototype it likely would have run into a hundred issues.  The primary one would have bene the last on the mind of the engineer. Which was how to look backwards while landing the aircraft during combat situations. As a mental exercise it almost looks like the perfect point defense fighter. It doesn’t require a runway and is fast enough to get to altitude in minutes.

  • LEROOOY

    How is the rotational force cancelled out? I don't see how the cockpit isn't spinning around in reverse at the same speed, unless there's some kind of giant counter-rotating weight inside the fuselage.

    • fodder650

      I'm trying to remember what they were using but this is one of those points I questioned myself. Not only this but once its in the air at low speed how is it controlled?

      I'll go look these up.

      • pj134

        Maximum speed: 621 mph (999 km/h; 540 kn)
        Never exceed speed: 1,730 mph (1,503 kn; 2,784 km/h)
        Minimum control speed: 150 mph (130 kn; 241 km/h)

        That's quite a gap.

        • Number_Six

          In truth the never exceed speed looks to be about 0.5mph.

        • fodder650

          Never exceed speed was over Mach 2? Thats a bit optimistic with the materials available. Also that minimum control speed worries me. You won't be landing at 150mph vertically.

          • Not twice, certainly.

          • fodder650

            Mach 1 is 762mph at sea level with it decreasing with altitude. That would put it over mach 2 as its crashing into the ground.

            Please correct me if I am wrong because I likely am.

          • pj134

            Piloting it would definitely keep you grounded.

    • CaptianNemo2001

      Piece of cake. You see where the rotors connect to the fuselage? On the 3-view on the upper right hand side we have a side view of the fuselage and the rotors connect to a piece that is shown as two vertical lines. This piece is connected to the rotors and the ram jets on the tips and ROTATES AROUND shaft and rotates independently of the fuselage.

      Think of it as a propeller with part of a plane behind the prop and part of the plane in front of the prop.

    • B72

      The rotational force on the prop is generated by the engines on the tips. Because of this,the only thing imparting a tendency to rotate to the fuselage is the friction of the bearings where the giant prop attaches.

      This friction generated rotational force can be opposed by the landing gear while on the ground, and by the tailplanes once sufficient forward motion has been achieved. The challenge comes in the transitional zone right after liftoff.

      In helicopter designs that use tip jets, the rotational force is so light that a tailrotor is not needed. In the design I am familiar with they simply added another (very small) tip jet on a stubby tail to perform this function.

  • texlenin

    Love me some Triebflugel! Make an interesting R/C model…..

    • fodder650

      I don't think I have seen anyone attempt to make one that way yet. I'm not even sure how you would set up the controls.

      • texlenin

        Heli control box? Only way I can think of….

      • pjreiss

        Pitch, Yaw and Throttle? Just looking at it, the only control surfaces seem to be in the tail. You could use something like a swash plate to add roll as well, but I don't know if it would even need it.

-->