Power-on stalls, other commercial diagrams.

[Kevincav]

Hi everyone, I'm going to be taking my commercial checkride soon in my 9a. I've heard mixed reactions and wanted to get other peoples opinions before I tried it. But I heard that 9a power on stalls are pretty nasty and could easily be put into a spin (even though the power off stalls are easy). Is this true or just a normal stall?

Another question, is there a place I could get fuel system diagrams for the 9a?

[sirlegin]

I cannot stall with power on. I just go in a nose up downward spiral

[Desert Rat]

If you're nose up, but in a descending spiral, I would submit that the wing is at least partially stalled, even if you didn't get a clean break/nose drop.

[Dan B]

My wife and I practice stall recognition and recovery on nearly flight. Power on stalls in our RV9 are uneventful. It takes approximately 25 degrees pitch up to induce a power-on stall. KEEP THE BALL IN THE MIDDLE at all times. At buffet, lower the pitch to about 10 degrees and she flies right out of the stall. (keep the ball in the middle)

The pitch-down caused by a stall with full flaps seems more eventful. Even so, it flies right out of the stall.

Recover from the stall by unloading the wings (lower pitch) first.
Do not use ailerons to level wings until above stall speed.

[Kevincav]

Thanks for clearing up my worries everyone.

[David Paule]

For the fuel system, get the RV-9/9A plans flash drive. It'll let you learn the fuel system as it was designed to be built. Some builders do some things differently, though, so it's worth pulling the cowl and starting with the tanks, trace out each line and each component so that you understand your own airplane.

Perhaps the builder might be able to offer some insight.

In general, the various components are, roughly in order:

Fuel tanks
Fuel valve
Electric fuel pump
Fuel filter or gascolator
Fuel flow sensor
carburetor or injector
Divider if injected
Engine

There are other parts that I didn't mention: the fuel vent system, the fuel pressure sensor and the electrical supply to the powered components. You can add the throttle to the list, too.

Dave

[Paul K]

In my 7, getting it to stall full power is a challenge. How much altitude do you want to gain? I find a 2/3 power stall is more positive but as mentioned already, keep the ball centered otherwise be ready for something upside down!

[rocketbob]

ACS specifies the applicant demonstrates power-on stalls no less than 65% power. So you do not need to be at full power to demonstrate power-on stalls. You will have to communicate this with the DPE prior to the maneuver.