2009 NIAA Model Focus

Dehavilland Chipmunk

Modeller: Ross MacKensie, North West Model Aircraft Club.

This 1/4 scale scratch built Mike Smart Designs Dehavilland Chipmunk took almost three years to build. It has a 102 inch wingspan and the fuselage measures approximately 72 inches. It is based on a full size aircraft which is at Roborough Airport in Plymouth, England and sports the colours of the Royal Navy Training Corps.

Ross certainly did a fantastic job with this model as it is extremely difficult to tell which is the model and which is the full size aircraft as seen in the above comparison.

Powered by a Super Tigre 3500 engine swinging a 20 x 8 prop, it isn't short on grunt either.

Infact Ross describes the model as being very docile and easy to fly. On its maiden flight the only adjustment required was a little down trim. The remaining control surfaces were all correct and made for an extremely uneventful initial flight, just what we all hope and pray for! Balancing the model took approximately 1lb of lead in the nose.

The model is hand painted using Japlac, dove grey and red, and is coated with a polyurethane clear varnish. Detail was paramount with this model and Ross made sure to include as much as possible including rivets and fake access panels.

To be sure that his pride and joy was as safe as possible he even gave the pilot a scale aeronautical map of the Londonderry area encase he got a little lost or his instruments failed mid flight.

The 102 inch wings have fully operational flaps and again with pilot safety in mind include foot grip panels.

Watching this Chipmunk in the air you could be excused for forgetting that it is infact a model. The engine gives of a very realistic purr and when flown in a scale manor, as Ross does extremely well, the model recreates all the best of the Dehavilland Chipmunk. No wonder this aircraft served with the RAF until 1996 when it was used for Air Experience Flights. Infact even today it is used by the British Historic Flights, - the RAF Battle of Britain Memorial Flight, the Royal Navy, and Army historic flights, to keep their pilots current on tail-wheel aircraft. Prince Philip took his first training flight in a Chipmunk way back in 1952 and the aircraft has served with the military of 21 countries including the UK, Canada and Ireland. Almost 1300 chipmunks were built with 1,000 of these being assembled in the UK initially at Hatfield Aerodrome and then later at Hawarden Aerodrome.

The full size aircraft has the following general characteristics;

Crew: 2, student & instructor
Length: 25 ft 5 in (7.75 m)
Wingspan: 34 ft 4 in (10.47 m)
Height: 7 ft in (2.1 m)
Wing area: 172 ft² (16.0 m²)
Empty weight: 1,517 lb (646 kg)
Loaded weight: 2,014 lb (953 kg)
Max takeoff weight: 2,200 lb (998 kg)
Powerplant: 1× de Havilland Gipsy Major 1C, 145 hp (108 kW)
Performance

Maximum speed: 120 kn, 138 mph at sea level (140 mph is also given) (222 km/h)
Cruise speed: 90 kn
Range: 225 NM (445 km)
Service ceiling: 15,800 ft (5200 m)
Rate of climb: 900 ft/min (274 m/min)
Wing loading: 11.709 lb/ft² (5.782 kg/m²)
Power/mass: 13.889 hp/lb (8.824 kW/kg)

If you have a model that you would like included in our model focus then send an email with your write-up and photos.

Top of Page