Flt's 4 through 8.
Objectives: 1. Finish breaking in the engine.
2. Fly at Max Gross weight.
3. Fly at full aft CG.
4. Fly at Redline.
5. Deep stall at Gross/aft condition.
6. Pull 3 G's at Gross aft Condition.
7. Establish min T.O. and Landing #'s.
Flight narrative: All the flights above went according to plan with the following exceptions. It was determined that the aircraft has a very aggressive deep stall/spin entry behavior. Intentional spins are recommended to be a prohibited maneuver. With the CG located anywhere from the middle of the envelope aft the airplane can easily "snap" into an unintentional spin that may not be recoverable. If you do recover the aircraft it will be after a minimum of 3 turns and you will loose a minimum of 2000 ft of altitude. The good news is that the aircraft give plenty of warning throughout the approach to stall and stall itself. If the recovery is initiated early in the process and no yaw is introduced this aircraft is very conventional in the initial stages of the stall. Great caution should be taken if you want to explore the deeper portions of the stall. This is all captured on the videotape and should be viewed by any pilots who are tempted to try deep stalls. Another area of concern that turned up during the flight tests was the Lancair supplied numbers for the stall/climb and glide areas. According to the POH, the best glide speed is 80 MPH with the flaps up. The flight-testing proved that the best glide for this aircraft is 90 KIAS with the flaps down 10 degrees. Along the same theme, the Lancair claimed stall speed is 57 MPH. Flight testing showed the stall speed to be 62 KIAS with the flaps down and 80 KIAS with the flaps UP.
Flight Test Summary:
Taxiing: The Lancair has no nose wheel steering. It is easy to control via differential braking. However, the brakes should be maintained with an almost paranoid zeal. If a brake feels "mushy" or weak do not continue the flight. If you have a brake failure in-flight it is doughtful that you could remain on the runway.
Run-up: This Lancair has a dual electronic ignition and while that may have some theoretical advantages, you must be familiar with the preflight check. Before flying you should be sure that both batteries and both alternators are working. The batteries are checked by cycling them prior to start. The alternators are cycled prior to take off.
Take off: Conventional take off characteristics. Flaps set at 20 degrees. Start rotation at 65 KIAS. Fly off at 70 KIAS. The aircraft does have a significant amount of torque and p-factor that is felt just at rotation. Bottom line is, you need to apply right rudder at rotation.
Climb: Climb at 80 KIAS until clear of obstacles, then bring flaps to 10 degrees and cruise climb at 120 KIAS. Above 10,000 ft cruise climb at 110 KIAS with the flaps at 10 degrees. A Word about the Wing: The flaps on the Lancair are designed to reflex up slightly when fully retracted. The advantage of this system is that this can reduce the drag slightly at high-indicated airspeeds. The disadvantage of that is at slower indicated airspeeds the wing must pull higher angles of attack to make up for the lost wing camber. At higher altitudes and gross weights the increased angles of attack result in much higher drag and worse performance in climb and glide and even cruise with the flaps up. Therefore, as a result of this flight test program it is recommended that for all climbs the flaps be set at the 10 degree down position until you are at the cruise altitude. This is also the recommended setting for best glide and even for cruise above 12,000 feet.
Cruise: Other than the caveat about the flaps being left slightly down at altitudes above 12,000 feet, cruise is conventional. The aircraft is positively stable in all axes. Turbulence penetration is good, especially when slowed to 140 KIAS and below.
Descent: Flaps up. Reduce power gradually. Descend at 300-500 fpm. Richen mixture. Glide: Flaps down 10 degrees. 90 KIAS. Glide ratio of 12:1.
Stalls: As long as the stall recovery is initiated at the first signs of buffet, they are conventional. If the aircraft is driven into a deeper stall expect sudden and dramatic wing drops. This may be followed by a spin entry that is uncommanded and possibly unrecoverable. The further aft the CG is the worse this behavior is. Deep stalls and intentional spins should be avoided.
Approach/Landing: Flaps should be down 20 degrees to full depending on the CG location. Due to the lack of elevator authority, when the CG is forward of center you can relieve some of the back stick pressure by using 1/2 flaps instead of full and leaving the power up slightly. Fly final at 90 KIAS and slow to 80 KIAS over the threshold. Add 10 KIAS to the speed if performing a no flap landing. Check the brakes prior to landing to ensure you have good pressures on both sides. If one of the brakes is bad, land with a crosswind on the side of the bad brake and on a grass runway if possible.
Flight test numbers for Lancair N711RG:
*Max gross weight at 5500 MSL and a proficient pilot.
*Sea level number should be approximately 15% better.
Rotation = 65 KIAS Liftoff = 75 KIAS
VX = 80 KIAS 1/2 flaps
VY = 90 KIAS 1/2 flaps
Climb rate at VY = 1200 fpm*
Min Take Off Roll = 2100 ft*
Min Landing Roll = 1600 ft*
Cruise climb below 10,000 = 120 KIAS 10 degrees flaps
Cruise climb above 10,000 = 110 KIAS 10 degrees flaps
Climb Performance @ 25sq. and 120 KIAS* To 3000 AGL = 4.5 min/10NM/2.5 gallons
To 6000 AGL = 9.5 min/22NM/5.5 gallons
Glide speed = 90 KIAS 10 degrees flaps Glide Ratio = 12/1
Stall speeds Power off, flaps up = 82 KIAS
VSO = Power off, flaps down = 62 KIAS
Stall with Power on, flaps up = 80 KIAS
Stall with Power on, flaps down = 60 KIAS
VNE = 220 KIAS
Normal Approach = 90 KIAS
Short field Approach = 80 KIAS
Max demonstrated crosswind = 25 knots
Flight Tested Cruise Numbers
@7500ft - 2500 rpm, 22 inches = 17 gph, 174 KTAS
2300 rpm, 20 inches = 14 gph, 160 KTAS
@9500ft - 2500 rpm, 20.5 inches = 14.8 gph, 170 KTAS
2400 rpm, 19 inches = 12.5 gph, 158 KTAS
@12,500 - 2600 rpm, 18 inches = 12.2 gph, 163 KTAS
2450 rpm, 17.5 inches = 11.5 gph, 158 KTAS
Link to HOME
Link to Lancair test page 1
Link to Lancair test pg 2