Hey gang,

 

Just an observation I've made, not sure if others are effected. When I follow the checklist procedures that require the fuel boost pump on/off selection, the checklist fails to acknowledge it properly. For example, the most recent case I've seen was during the after landing list. Yes I know it's short but I do like to view them sometimes to make sure I'm not forgetting something. On that list it instructs to turn off the boost pump. Before I have the chance to mouse over and toggle the switch to the 'off' position, the checklist acknowledged it was already completed and closed.

 

Another case if I recall correctly, during the before takeoff list, it doesn't acknowledge that the boost pump switch is on, or toggled to on, and the list remains open.

 

 

Cheers

 

Darryl

Can't say I've payed much attention to the fuel pump switch. I don't even know what it does in the context of Flight.

Are you sure the boost was on when you did the after landing list? If the list sees something is done already, it simply moves on.

 

About the list not registering things and staying open: that happens to me all the time, at random. The checklist are a bit buggy.

The fuel pump switch on the Maule is a known problem.

 

Hook

Are you sure the boost was on when you did the after landing list? If the list sees something is done already, it simply moves on.

 

About the list not registering things and staying open: that happens to me all the time, at random. The checklist are a bit buggy.

 

Yes the boost was toggled 'on' during the after landing list. That is one of the problems, is that the list 'moved on' when the action wasn't yet completed.

 

 

@ Hook, thanks for that bit of info.

What is the fuel pump supposed to do? Planes seem to fly without it just fine.

What is the fuel pump supposed to do? Planes seem to fly without it just fine.

 

Oh man... I might get this wrong... someone maybe correct me? I believe it's to facilitate fuel flow since maybe it's normally gravity fed. So during takeoff and landing you want to ensure proper fuel flow? Does that sound about right for anyone that really knows? Yes the planes will operate just fine without it for the most part.

I can't speak for the Maule but on some aircraft the using an electric fuel pump is not an option. I believe this is the case with many low wings.

 

Being a high wing, I'm guessing that the checklist calls for it to avoid fuel starvation when the engine us running at high power during a critical phase of flight. This may save your butt if the engine driven pump fails.

On my piper Cherookee which is low wing, there is a mechanical pump that pump fuel to the carburator. The electric pump in installed in series with the mechanical one and is put ON as a safety backup in case the mechanical pump break in a critical moment during take-off or landing. Fuel starvation when in initial climb is particularly critical as if you dont push immediately on the yoke when power is loss to maintain a safe airspeed, you are running very fast in the stalling zone and potential wing drop and spin at low height which is a deadly situation. Final approach is also critical even if youre in a better position with the nose down or toward the horizon. If your are maintaining some power to make the threshold, a suddend power loss can make you touch short of the runway or transform your lovely plane in tree and weed cutter...

 

It is also common procedure to put the electric pump ON while switching from left to right tank or right to left.

 

This thread come timely as Im just reading my POH this afternoon in preparation for the summer season. I just get out the plane yesterday from its winter storage (fun begin.... ).

 

My Piper POH page 2-7 states "An auxiliary electric fuel pump is provided in case of the failure of the engine driven pump. The electric pump should be ON for all takeoffs and landings and when switching tanks."

 

It seem to be the same on Maule from this thread on Maulepilot.org. They argue about the real interest of putting it on and some mention that you just need to put them on if the mechanical pump fail. I disagree as when it happens, you have no time to think, better have your backup already ON and providing you the extra safety margin you need. I agree however that you should not leave it on all time as it is not designed for continuous operation.

 

http://forum.avsim.net/topic/369154-maule-checklist-fuel-pump-switch/page__pid__2330786#entry2330786

 

Fly safe....... put all chance on your side... that's part of the simulation fun.....

Yes. Thats my understanding also. Fuel boost is a backup for takeoff and landing. Typically an engine will suck fuel on its own once running, so you turn it off once at a safe altitude to spare the electric motor. Typically it does not hurt to leave it on, but some fuel pumps have been known to over-heat, so most pilots turn them off since its not needed. Some aircraft like the Republic Seabee MUST have the fuel pumps on at all times since the fuel tank is well under the engine. It even has TWO fuel pumps, one for backup.

fuel pumps...

 

Is the Flight Maule a carb or fuel injected model? I couldn't tell from the low rez panel pic I've seen. Fuel injection requires a lot more fuel pressure than a carb, and gravity won't do it. Somewhere along the lines of 26 psi, versus 4-6 psi for a carburetor. Older Cessnas used carbs, and many of their engines had no mechanical fuel pump on the engine. It was all gravity from the two wing tanks into a small header tank. When Cessna restarted production of single engine high wings, they went with fuel injected Lycomings. Low wings require the mechanical and backup electric fuel pump to move fuel to the carb bowl, which is higher than the wing tank.

Thanks for your help. What is the Pitot heat used for? Thanks

Thanks for your help. What it the Pitot heat used for? Thanks

 

A built in electric heating filament, that heats the pitot tube, any time you suspect the possibility of icing. The tube is usually under the wing, out of the prop arc, but can be mounted on the nose, fuselage, etc. It picks up air pressure to run the airspeed indicator.

The pitot tube is the forward-facing probe that collects ram-air for your airspeed indicator. They are often equipped with an electric heater to prevent ice buildup from blocking the opening, which would cause erroneous airspeed indications.

Many aircraft have more than one pitot probe and some aircraft call for the pitot heat to be applied at all times from takeoff to landing, especially those that operate at high altitudes. Also, on the ground, it's common practice to cover the probes to prevent spiders & the like from nesting in them and clogging up your pitot system. Just make sure your probes are cool before putting the cover on or you could burn the cover, or worse yet, your hand. (Personal knowledge here. :Hypnotized: )

 

The complimentary part to the pitot system is the static system, which is what the altimeter operates off of. Together, they make up the pitot-static system. Static ports are usually mounted flush with the surface of the fuselage and look like a metallic disk with several holes in it.

 

WildBill