233 Kts, FL230, 26 Minutes From Brake Release... Wow! Part Six

It Sure Goes fast… But Does It Go Slow?

Stalls are a joke. Both elevator and rudder are limited (with an actual rudder limiter built into the aircraft systems) so as to keep one out of trouble (something I understand the reasoning behind but personally do NOT care for). This is NOT a criticism of the airplane, because this aspect of the design will, no doubt, keep some poorly-trained pilot from doing something stupid. I just hate anything that takes control away from the pilot....

A full power-off, clean stall is a non-event, especially if approached at anything less than a degree per second pitch rate. Just under 70 kts, the C400 shudders with a barely discernible high frequency buffet and the nose refuses to rise to an inefficient angle of attack. Approach a stall with a more aggressive rate (without aggressive loading) and the bird simply reaches a critical angle (often about 10-12 degrees pitch up) and then.... comes down. OK: maybe there’s a little waffling, but there is no asymmetrical behavior and NO games. Do it with all 310 ponies at full gallop and the bird still doesn’t want to do much but turn a little in sympathy with the torque, though there is still enough rudder to keep the ball centered. I could not get it to break with the weight distribution we had on our test flight. I’d love to try it at aft CG, though, since the Lancair manual indicates that the effect is not quite as benign (and the factory requires new C400 pilots to be trained in this area, to boot).

With a notch of flaps, the stall settles into the low 60s, remains wholly symmetrical, and still won’t break worth a damn. I might as well have brought a lunch and had a sandwich, so bored were we with what was going on. Control response at stall remains quite agile, with excellent rudder and roll authority right up through what appeared to be as much of a buffet as we were going to get. With full flaps, it becomes obvious that the landing flaps throw out a LOT of drag and it becomes VERY difficult to get the nose to approach anything resulting in a critical angle of attack. What happens is a slightly more solid high frequency buffet with a slightly more notable amplitude and a bit of nose nodding until you decide the whole thing is stupid. About the only negative note (a small one), I found was a slight force drop-off near stall... resulting in about 10-15% reduction in aft stick force. Once again, everything stays stable, symmetrical and controllable. All recoveries occur rapidly with simple lessening of pitch pressure.

I Feel The Need… The Need To Breathe

The Lancair 400 is a heavy breather and can operate at altitudes that require supplemental oxygen to keep the pilot operating legally and efficiently. As you may recall, oxygen is required to be used by pilots above 12,500 ft for any flight time exceeding 30 minutes and full-time above 14,000 ft. Lancair recommends that if climbing to an altitude where oxygen will be required, that at approximately 10,000 ft, the pilot should begin using the oxygen. Passengers must have oxygen available above 15,000 ft.

The Lancair factory oxygen system is built by Precise Flight. It consists of three, 14 cu ft oxygen bottles tucked into the right wing, a regulator/valve assembly, a filler port in the aft baggage compartment, an overpressure protection device, a guarded overhead emergency manual valve, an overhead distribution manifold, a display controller, and associated lines, fittings, valves, and sensors. The total oxygen capacity of the system is 42 cu. Ft. with a maximum oxygen cylinder pressure is 2000 psi. The low pressure operating pressure is 20 to 33 psi. The bottles are interconnected by bottle fittings and the high-pressure stainless steel lines to the high-pressure manifold of the regulator valve assembly. Attached to both the high pressure manifold and the low pressure distribution manifold are electronic pressure transducers to measure the oxygen pressure at the respective locations. An annunciator light provides warning information to the pilot.

The oxygen system will light an annunciator if the system has not been activated above approximately 12,000 ft PA, there is inadequate quantity of oxygen or if the oxygen outlet pressure is up to snuff for proper operation.

The Oxygen system is simply designed and seems quite easy to operate. A prominent three-position master switch on the display may set to the ON, OFF and DISP modes. The ON position engages the solenoid and will display the High Pressure and Low Pressure values. The OFF position will disengage the solenoid and there will be no display. The DISP mode has a quick check function that displays only the High Pressure and Low Pressure values for preflight and filling operations. The DISP mode is used to determine whether or not the bottles need to be refilled or for filling purposes as this provides the fill level, or high-pressure reading. A fault light alerts the pilot to a problem with the electrical connection to the regulator/valve assembly. The oxygen display graphically details the pressure state to the pilot, When the lights are green, all is well with the world and you should be breathing naturally. Red lights indicate that something is amiss. When the oxygen switch is in the on position the display will illuminate and indicate the quantity of oxygen available, as well as the system pressure.

To Be Continued...

FMI: www.lancair.com/certified