|A Pilots Report on Flying The DAIR-100 powered Luscombe|
Climbing aboard requires a bit of agility particularly when well wrapped against the freezing temperatures we have experienced recently. Buckling the 4 point harness is designed to test the skills of a contortionist, as the straps need a bit of adjusting from a previous occupant. Snug is an understatement when squeezed in next to my 14 stone passenger.
Starting is simply a matter of ensuring the stop control is pulled off, the throttle cracked open and the starter button pressed. The engine bursts into life after a couple of revolutions and the throttle is adjusted to a fast idle, circa 600 rpm. The oil pressure comes up almost instantaneously and after 30 seconds the throttle can be opened for taxi.The home based strip is a bit rough and 1500 rpm or so are needed to commence taxi.
A touch of salsa dancing on the rudder pedals and we're lined up at the end of the strip. A check on full and free movement and the fuel status, trim set for take off, t's and p's showing positive and its 'ball (singular) to the wall'. We are airborne within 100 metres and climbing at an impossibly steep angle to our cruise altitude of 6000ft. The engine seems to run smoother at anything over 3000ft, probably due to the fact that excess air is available at sea level. This ensures a smoke free exhaust at altitude with full throttle. The throttle should be reduced above 8000 ft density altitude to prevent over fuelling. The simple injection pump does not have altitude compensation to reduce fuel as the air density decreases.
We level off at 6000 ft maintaining full rated rpm of 2500 and the speed quickly increases to 136 mph, racing Luscombe performance from an old ragwing. The draughts up here are noticeable with freezing air leaking in all over the place. Someone needs to pay a bit of attention to the interior. Does that come under the auspices of the PFA? After some fun doing steep turns and stalls, no messing about with throttle here just open it or shut it, we cruise along at 120mph and 2200rpm for a while. We then gradually reduce power to fly level at minimum setting. A relaxing 1750 rpm keeps us up there still making 80ish mph.
Finally after another race track at 2500 rpm we close the throttle to idle stick the nose down and wait patiently for the ground to come up and meet us. No worries about shock cooling this engine. Crossing the runway at right angles and 800ft we make a gentle sweeping turn to arrive at the threshold 20 ft or so off the ground sinking onto the runway stick now fully back. Sounds easy but I fibbed a bit. Some aggressive sideslip was required on finals to get us down the extra 100 ft. Someone had overestimated the sink.
We pull G-DAIR tail first back into the hangar and shoot off for a hot cup of tea and some cake to discuss the jet fuelled compression ignition adventure.
When will yours happen ?