Kit No. PM-224
Decals: One version – Luftwaffe
Comments: Simple construction, engraved panel lines, basic cockpit
The Lippisch P.13a was an experimental ramjet-powered delta wing interceptor designed in late 1944 by Dr. Alexander Lippisch, who designed the Messerschmitt Me 163 Komet. The aircraft never entered production, but did make it to the glider stage after extensive wind tunnel testing indicated the design had extraordinary stability up to speeds in the range of Mach 2.6. It was a seminal design in that it exerted a strong influence on the post-war design of delta-winged combat aircraft.
As conventional fuels were in extremely short supply by late 1944, Lippisch proposed that the P.13a be powered by coal. Initially, it was proposed that a wire-mesh basket holding coal be mounted behind a nose air intake, protruding slightly into the airflow and ignited by a gas burner. Following wind-tunnel testing of the ramjet and the coal basket, modifications were incorporated to provide more efficient combustion.
The coal was to take the form of small granules instead of irregular lumps, to produce a controlled and even burn, and the basket was altered to a mesh drum revolving on a vertical axis at 60 rpm. A jet of flame from tanks of bottled gas would fire into the basket once the P.13a had reached operating speed (above 320 km/h), whether by using a rocket to assist takeoff or by being towed.
The air passing through the ramjet would take the fumes from the burning coal towards the rear where they would mix under high pressure with clean air taken from a separate intake. The resulting mixture of gas would then be directed out through a rear nozzle to provide thrust. A burner and drum were built and tested successfully in Vienna by the design team before the end of the war.
It is not known what armament would have been carried by the P.13a; the MK 103 cannon would have been too large and heavy for such a small aircraft and it is possible that one or two large-calibre machine guns would have been used.
At the end of the war even the prototype DM-1 test glider had not been finished when it was captured by U.S. forces. Lippisch’s team was ordered to complete it, and it was then shipped to the USA where it was test-flown. The results were reportedly very positive and the lessons learned were incorporated into subsequent research aircraft, particularly the Convair XF-92.
Film footage exists which shows a gliding test of a scaled-down model of the P.13a. These tests began in May 1944 at Spitzerberg, near Vienna. After the war, Lippisch, working with American aircraft designer Convair, developed and tested the XF-92 based on his designs, leading to the eventual adoption of the F-102 Delta Dagger and its successor, the F-106 Delta Dart.
PM Models’ Lippisch P.13a is injection molded in grey and consists of 11 parts, including a single unframed clear part for the canopy. The cockpit is situated within the vertical tail and features only two parts: a seat back and a control stick. The delta wing of the P.13a is merged into the fuselage itself, so the upper and lower halves of the wing, along with the two halves of the rather thin tail form the entire airframe. The parts for a separate towing dolly complete the kit. The kit features engraved panel lines, and the instructions include a painting guide (calling out Tamiya, Humbrol, Revell and XtraColor numbers) for a late-war Luftwaffe scheme of Brown Violet/RLM 81 and Dark Green/RLM 82 over Hellgrau/RLM 65, with a mottled effect on the vertical tail. An interesting omission from the kit, given that the P.13a had a ramjet powerplant, is that there is no part for any mesh screen or baffles in the intake, as there were for the V-1 flying bomb, which had an identical powerplant.
This is a quick weekend kit of a Luft ’46 aircraft and should be an interesting addition to any modeler’s collection. It is also of historical interest given its influence on post-war aircraft design. While not highly detailed, it will not be a time-consuming build, and represents an aircraft that was barely off the drawing boards by war’s end. Highly recommended.