Deer changes plans: Transition to Complex

After a brand new engine in the Diamond,  things looked good.  30 hours into the break in period, there was still an odd differential in EGT for cylinder one.  The last I heard concerning this issue is identification of a missing seal.  I was getting excited for a VFR night flight to fulfill another commercial requirement.  Four days before the flight, another club member had an unfortunate mishap with a deer during a night landing.  The front nose wheel strut was damaged.  Everything else looked ok.  However, the prop did make a mess of the deer.  If I get a chance, I will post some pictures.  Not pretty.  To be conservative, the engine is going to be stripped down and reinspected for an internal damage.

I decided to minimize my down time and begin the transition to complex aircraft.  This work is applicable to the ten hours of complex training required for commercial certification.  If all goes well, I should be flying a Piper Arrow PA-28r-200.  I like to be prepared for such adventures.  I downloaded a POH for the aircraft and began my studies.  Naturally, my focus is on the gear operation.  Many of the other procedures are not that different from the Diamond.

The Arrow has a hydraulic gear system.  It uses pressure membranes to control operations.   One nice property of the system is an automatic gear release when the aircraft slows below 105 with less than 14.5 inches of manifold pressure.  Furthermore,  the gear cannot be retracted at air speeds less than 85 knots.   The speed of gear down operations actually varies between 85 and 105 depending on power and altitude.  This brings about two questions: (1) How does one practice stalls and chandelles with out the automatic lowering of the gear and (2) how does one retract the gear early when necessary in certain a short field take-off settings when speed is below 85 knots?  The answer is the same for both.  There is a manual gear level between the seats that has an 'override' by pulling the lever up.  The level also serves in a preliminary step to force a gear down when the gear switch result in a gear release.  There is a latch to hold the lever in the up position.  Naturally, this should be temporary to avoid overriding the safety feature.

The lever is accompanied by a blinking warning light that is operational in situations where the gear switch disagrees with the situation of the airplane.  For example, a gear up when the plane is on the ground or manifold pressure is below 14 inches, or when the override lever is engaged.  The plane is accompanied by a gear horn.  The lights and the horn are electrical.

Lowering the level to floor is used to release the gear.  It used when the gear switch fails to lower the gear, normally indicated by the absence of three lit green lights.

The gear can be lowered at or below 125 IAS.  A normal approach includes a gear down prior to final, lowered as part of the pre-landing checklist.  Final approach speed is no less than 90 knots to the flare.  I have not looked at the performance charts in great detail to recall the specific speed variations according to weight.

Raising the gear naturally occurs after establishing a stable climb at or above 85 knots.    Normal climb speed is 95 knots gear down and 100 knots gear up.

Other interesting properties of the Arrow that stood out at first read are as follows.

• The Stall Horn is electric
• Panel should be dim during the day to not mask the gear lights.
• The systems 14 volts, not 28 like the C172.
• The Arrow is accompanied by a secondary vacuum system.
• High altitude operations affect the gear system due to the pressure sensors.   This does have implications in high altitude airports. 
• The hand brake use the same brake fluid reservoir as the toe brakes.  

If all things go according to plan including weather and a healthy Arrow, I will be have my first flight tomorrow.   I plan on writing up any misconceptions and new lessons in my next blog entry.  In addition, I plan on doing a performance comparison.  From what I understand, flying the Arrow is not as sensitive as the Diamond.  Flying the Diamond requires very little stick pressure, even on the flare.   Consider that a flare and landing with a C172 ends with the wheels touching the ground when the yoke is back as far as it can go.