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FLIGHT-TEST par Jean CAILLARDFormer Pilot of Test-(Avec the pleasant authorization of his author, this article east publishes in extenso and is protege by the Law of the Copyright.)

The "Bulldog" was made in 1968/1969 by the "BEAGLE" company based on the Military version of the Beagle Pup whose first flight dated backe to 19 May 1967. 328 were built, it was used as a training aircraft by Sweden, Malaysia, Kenya ( 100 series ), Ghana, Nigeria, and the RAF ( 120 series ). The cockpit layout differed according to the needs of each country. The example based in La Baule ( MAPICA ) and registered F-AZTF, corresponds to the RAF version.

Layout of Pilot's cockpit : As with most of Britsh aircraft, one has the impression that there is more room inside, than is at first visible from the outside! Two people of above average size are at eaze, both height and shoulder width. The seats are not adjustable, ( Except for the seat backs which can be inclined forwards and backwards ) The canopy has a jettison handle which can be actioned in flight, the aircraft is authorised aerobatics - +6g, -3g. The rudder bar is adjustable on both sides, pilot and co-pilot. Each rudder pedal is adjusted individually. The toe lifts a blocking lever and the pedal moves towards the pilot. The manoeuver is not at first simple, both feet are required to move the pedal away from the pilot, one to hold the locking mechanisme, the other to push the pedal. There is no indication of symetry of position. One throttle lever is well positioned on the central console, it also has the mixture control, trim control - tab and rudder, and for the flaps ( whose intermediate position at 10°, is insufficient for my personal taste ).

No remarks on the instrumentation or swithches. For larger pilots the row of breakers is invisible once seated. The first time seated with two people on board, one is surprised by the nose-up attitude of the aircraft ( at this C of G setting ) which leaves poor forward visibility .... but once the engineis running, the nose dips enough for the visibility to become excellent..

In flight impressions: flight in calm air, AUW 986 kg, ( 2 pilots and 122 l of fuel ) QFE 992 mb. Start up, no comments, ( Engine Lycoming of 200 hp injection ( Inverted flight ) Taxying :very easy - the aircraft is docile and seems liitle affected by wind conditions - braking, easy to regulate.

Take-off : Flaps 10°- Trim in the centre of the range - Rudder Trim 10° to the right. Open the throttle with brakes fully applied. On release of brakes the acceleration is crisp without any tendance to yaw, and take off is around 60 kt. 80 kt is rapidly reached without any need to change the trip, climb speed is de +900 ft/mn.

Climb : In normal climb - flaps 0° - 2500 rpm admission 25" VI = 80 kt - trims unchanged, ball in the middle, the climb between 1500' and 2500' id more than 660 ft/mn , bringing the rudder trim to the 0° position, no change is felt.

Cruise : All flight test were carried out in the following conditions : - flaps 0°, pressure altitude 4000', Temp +4°c, engine 2300 rpm, admission 23', VI stabilised at 109 kt. Longitudinal : the aircraft, well trimmed, easily maintains it's speed. Stick forces are light for any change ( + or - 1kg for + or - 10 kt ) but noticable because friction in the controls are very weak. The phygoide is well dampened ( period of 30 secs ). Stick forces in the turn ( up to n=2 ) are light ( 2kg estimated at 60° )

In reaching the VNEa fank and real dive is required to make the ASI respond. Stick force is noticable ( estimated 4 kg for 160 kt ) not too heavy and homogeneous with the other flight conditions.

Transversal: Directional stability is frank and clear.
Lateral stability, is indifferent. In a stabilised side-slip, the crossed control is correct, and the forces are normal with the side-slip but little aileron is needed for a lot of rudder ( therefore when the aileron is released the lower wing has no tendency to rise ). The stabilised sid-slip causes very little longitudinal reaction ( tendancy to dive in right hand turn, nothing in side-slip to the left ). Roll rate with rudder bar blocked, is greater than 30° /sec..

Clean stall throttle closed. Initial conditions, aircraft trimmed at 75kt ( trim indicator set at the limit of "nose-up" for take off, so still far from the end stop ). Rudder trip 0°, throttle fully closed. Good lateral control remains throuugh the deceleration stall warning at 61 kt. A little natural buffeting towards 55 kt. Little longitudinat movement at 51 kt stick fully back on the stop. No transversal phenomena under these conditions. Immediate control.

Change of configuration: at VI = 100kt in level flight - aircraft trimmed, flaps 10°- stick force almost nil. at VI = 80kt in level flight - Aircraft rimmed, flaps from 10° to 45°: stick force almost nil. No reduction in speed.

Landing configuration : The same flight tests were carried out as is cruise, but with flaps at 45° under the following conditions : - pressure altitude between 2500' to 1500' - propeller fully fine admission at 17" VI stabilised at 70 kt . The results are similar and the longitudinal stability frank. Fore and aft stick forces ( + or - 0,5 kg for + or - 10 kt ) and aileron are lower and spiral stability indifferent. Roll rate ( rudder blocked ) is around 25°/sec ( a little better to the left than to the right ).

Stall, throttle close flaps 45° Aircraft rimmed to 70 kt. Almost all ther trim movement is required, Deceleration well controled, stall warning at 55 kt. Light buffeteing in calm air at 50 kt, the nose dips at between 46kt / 47 kt, stick fully back, descent shows -1100'/mn - immediate control.

Go around a) - From 70 kt - throttle closed and trim almost against the nose-up stop : an outer limit situation Throttle to fully open , a frank push is required on the stick - 5 to 6 kg to maintain 70kt, no tendency to yaw the variometer steadies on + 500ft/mn b) - From 80 kt - To full throttle - Aircraft rimmed ( trim returned to anear the zero mark ) flaps can be retracted from 45° to 0° without any tndency for the speed to move, and without yaw.

Landing: Final approach at 70 kt - flaps 45° - reduce power at the start of the flare : no comment. Only precaution to take, maintain the nose wheel off the runway as long as possible to avoid any possibility of nose-wheel shimmy..

Conclusion : The Bulldog is a pleasant and obediant aircraft. the excellent harmony of the controls give light forces, while conseving good precision. The trim only really leaves the zero position with the flaps at 45° - throttle fully closed. ( a configuration little used in flight ) However the aircraft must be corectly trimmed for the approach and pilot input must be gentle, because the loss of efforst at this stage can lead to pilot induced oscillations, for this reason one can retain the actual stall warning settings, though this apperars to be slightly higher than the manufacturers setting. We were not able to notice the utility of the rudder trim ( even though the aircraft is short coupled, the differences in yaw at different power settings were insignificant ) Is it possible that it's existance is due to the aircraft training role ? The crossed controls in side-slip tend towards giving the aircraft a good reputation for cross-wind landings.

Copyright Mapica - Jean Caillard.