PA-28-200R Landing gear

[IrishFlyer]

Hi Guys,

Sorry but the POH for this aircraft is useless. I have been getting to many contradicting answers regarding the gear system for said aircraft and I need a quick definitive answer. How many micro switches and where? And isn’t there only one squat switch on the left main gear?

Also have any of you guys heard about aircraft manufacturers designing a slight twist in the tail and or vertical stabilizer to counteract torque effects?

Thanks very much,

IF

 

[greyhound]

Gear....

P-28R-200 has
A.squatswich on left main gear.(disables gear operation on ground)
B.Microswitch on the throttle quadrant. (Activates horn Below 14" MP with gear up.)
C.Microswitch on flaps. (Activates horn beyond 10 degrees flaps with gear up.)
D You have three down-limit switches and obviously three up-limit switches.
These basically tell the hydraulic pump when to stop pumping hydraulic fluid to the actuator cylinders on all three gears.

I've heard of the vertical stabilizer thing. Whether it's found on the Arrow? I don't know.

I've also heard mounting the engine at a slight angle off-sets torque.
Which manufacturers do this? I don't know.

 

[unreal]

I've also heard mounting the engine at a slight angle off-sets torque.
Which manufacturers do this? I don't know.

I've heard of this, but in a bit different context. If you take a look at the Arrow's prop from the side, you'll see that the longitudinal axis of the airplane is not 100% perpendicular to the prop arc. In fact, the engine appears that it's tilted slightly down. This was done to keep the propeller somewhat perpendicular to the relative wind while the aircraft is flying with a normal AOA. This could help reduce p-factor, but I don't think torque would be affected.

 

[IrishFlyer]

Thanks guys - very helpfull.

IF

 

[Tinstaafl]

Safe to say we're all familiar with the yaw left/pitch up characteristics for a clockwise rotating propeller when the engine is at high power. It's caused by several factors including slip stream & P-factor. Rudder, fin &/or engine thrust line offsets are common methods used to reduce the yaw &/or pitch couples associated with propeller slipstream & P-factor.

Usually the correction is arranged so that it cancels the yaw at cruise speed & power setting(s). Of course the corrective effect from aerodynamic solutions may still be significant even when the power setting is low and the correction is not needed ie with an offset fin or rudder. This means that the correction will be insufficient to completely counter the yaw at low speed/high power settings, and overcorrect at high speed/high power settings - unless there's a cockpit adjustable rudder trim which lets the pilot increase or decrease the rudder's yawing force without having to hold continuous pressure on the pedals.

 

[Flyboy758]

What exactly is a microswitch?

 

[Tinstaafl]

A type of pressure activated switch. It has a protrusion that is held in an extended position by spring pressure. When a moving part reaches it's desired position a contact pad presses against the protrusion on the microswitch, pushing it in. The part of the protrusion inside the switch can be wired so that an electrical contact is made with the protrusion extended and broken when pressed in, or so there is no circuit in the extended position & a circuit is made when the switch is pressed in.

If you've ever seen the switch on your car door that activates the interior light when the door is opened then you've seen a type of microswitch.

 

[freeflyer14]

I've also heard mounting the engine at a slight angle off-sets torque.
Which manufacturers do this? I don't know.

The Beech Musketeer does this for sure, don't know of many others off hand.

 

[EDUC8-or]

I know the Cessna 172 has a greater angle of incidence on the left wing than the right to counteract torque. That's why the stall warning is on the left wing, it may indicate a stall before the airplane has fully stalled.

 

[Tinstaafl]

What's your source of information about the L-R incidence difference? I can find no reference to it.