Bell/Boeing D340 « Pointer » tilt-rotor demonstrator (TRUV)

[hesham]

Hi,

http://books.google.com.eg/books?id=IuQDAAAAMBAJ&pg=PA87&dq=boeing+RPV&hl=ar&ei=CM2lTNmBDMaUOuaOsKwC&sa=X&oi=book_result&ct=result&resnum=8&ved=0CEkQ6AEwBw#v=onepage&q&f=true

 

[Stargazer]

This is, of course, the unbuilt Bell D-340 Pointer VTOL UAV.

 

[AeroFranz]

does anyone know if there is a direct lineage between Pointer and Eagle Eye?

 

[Stargazer]

More of an uncle than a father, really. The Pointer was a sub-scale proof-of-concept for the V-22. The Eagle Eye is a UAV which draws heavily on Bell's tilt-rotor experience on the V-15 and V-22 programs. But I agree that there is definitely a family resemblance there...

 

[AeroFranz]

Sans blague?
I didn't think of making the connection between the Osprey and this...

Where does the Pointer fit in the Bell chronology compared to XV-15? Was it prior?
There are substantial differences between pointer and eagle eye, but I bet the powertrain was VERY similar.

 

[Stargazer]

All things considered (and judging from the mention "UAV" on the tail) I wonder if we shouldn't dismiss the sources which claim that Pointer was a "1/5th scale flying model of V-22 configuration." Not only the XV-15 was already pretty much a flying demonstrator for the Osprey, but the V-22 was also aerodynamically tested with subscale wind tunnel models.

After researching the matter further (and there is now a lot more to be found on the web than when I looked into it a few months ago), the Bell-Boeing D-340 Pointer (not to be mistaken for the later Aerovironment UAV of the same name) was a much more direct genitor of the Eagle Eye than I thought. The Eagle Eye UAV is even said to have been "based partially" on the Bell-Boeing Pointer UAV.

[More below]

 

[Stargazer]

The tilt-rotor UAV was originally conceived in a joint effort between Bell Helicopter Textron and Boeing Helicopter, begun in 1986, to develop a V/STOL short range surveillance/reconnaissance drone for the U.S. Army, patterned on the V-22 Osprey's tiltrotor technology. The two companies decided to spend $700,000 of internal research and development funds to build a tilt-rotor RPV weighing less than one per cent of the V-22 Osprey, also in development at the time, on which it was to be patterned.

Thanks to the vertical take-off and landing mode, this unmanned vehicle could carry more delicate loads than conventional RPVs. It could cruise at high speeds, loiter in an orbital pattern and hover for hours over a fixed position. Also the risks of damaging the RPV during recovery were far lower. The VTOL capability of its propulsion system obviated all launch and recovery equipment without forfeiture of high forward speeds during critical mission segments; in particular, shipboard operations could be readily conducted from small deck areas at sea.

Development of the D-340, in effect the world's first tiltrotor unmanned air vehicle, proceeded throughout 1987. The Pointer was of all-composite construction. Due to its light weight, the power-plant chosen was a 95 hp Suzuki snowmobile engine. Bell built the propeller/rotors and drive system while Boeing constructed the fuselage and flight-control system, which apparently consisted in "off-the-shelf" r/c equipment familiar to any model aircraft enthusiast.

The Pointer made its first public appearance at Farnborough in September 1988 and flew for the first time on 21 November 1988, but the partnership ended in September 1989 when Boeing dropped out of the program after only 12½ hours of flight trials and 40 hours of wind tunnel testing. Bell continued on its own, and developed the Eagle Eye TRUV (Tilt-Rotor Unmanned Vehicle) under the TRUS program for an interoperable VTOL UAV, with the first of two TR911X seven-eighths scale prototypes making its initial flight on 10 July 1993. The prop rotors of the Eagle Eye, each with three glassfibre-reinforced plastic blades, are said to be have been based on those on Bell's Pointer UAV and on a Bell Boeing V-22 windtunnel model.

Technical data for the Pointer:

• wingspan, spinner centerlines: 3.25 m
• width, blades turning: 5.61 m
• length of fuselage: 4.06 m
• height, top of spinner: 1.67 m
• rotor diameter: 2.36 m
• loaded weight: 250 kg
• empty weight: 185 kg
• maximum speed: 297 km per hour (160 knots)
• cruising speed: 260 km per hour
• hover ceiling in ground effect: 2750 m
• hover ceiling outside ground effect: 2300 m
• endurance: 7 hours
• combat radius: 185 km

Sources and useful reads:

• http://legacy.vtol.org/uavpaper/NavyUAV.htm
• http://www.flickr.com/photos/runway27r/1563586956/
• The Naval Institute guide to the ships and aircraft of the U.S. fleet, by Norman Polmar (U.S. Naval Institute, 2005)
• Flight International, March 9, 1993
• "Unmanned Air Vehicle/Remotely Piloted Vehicle Analysis for Lethal UAV/RPV", by Burke R. Kaltenberger (September 1993)
• Bell Aircraft since 1935, by A. J. Pelletier (Putnam, 1992)
• "Pointer, A New Concept for RPV Air Vehicles", Automation Application for Rotorcraft (AIAA Technical Library # IAA8902, April 1988)

 

[AeroFranz]

Nice biography, well done!