Help! Multi Comm Checkride Coming Up!

[tarp]

I read quickly but I didn't see anything about the oral. Our nearby D.E. says that the oral is 55% of the ride. Know your airplane better than the company that built it. That's a big difference between a Private Single and Comm Multi. You didn't say which airplane, but let's assume the mighty Seminole is involved. A fair question would be - Where does the fuel for the Janitrol Heater come from? If the engine failed on the side the fuel is being pumped from would the Janitrol Heater fail? (I know some people would say that you don't need any more heat in the cockpit if the engine just died!)

My point is - you really have to be in the POH / Airplane Manual.
Know you complex systems cold - Landing Gear, hydraulics, brakes, crossfeed & other fuel system peculiarities, electrical, etc.

Weight and balance - you will be a commercial pilot. Regs - you will be a commercial pilot that might be approached to do flying.

The flying part is easy but made harder if you've just been struggling for two hours worth of oral to get answers out.

Good luck.

 

[PHXAviator]

I'll Be Using an Apache

Thanks everyone for the advice. It's greatly appreciated!

I'll be using an Apache for my checkride. I've been studying the POH religiously, so I shouldn't have a problem with systems. I do need to double check how the nose heater gets its fuel. Great question!

I'll be sure to let the curious know how I do on the checkride.

PHXAviator

 

[bigD]

Oh yeah - the oral!

I took my multi-comm add-on relatively recently, so the DE's questions on the oral are still fresh in my mind. I already had my single engine commercial, so I didn't get asked anything but what was specifically related to twins, but here's what I was asked (I flew a Duchess, by the way):

What is a critical engine, and what are the factors that make one engine more 'critical' than the other?

What is Vmc? How are the aircraft manufacturers required to set up the aircraft and what conditions must be present in determining Vmc? How is Vmc affected and what can we do on the ground, and in the air, to lower it? Why must you be careful of altitude when doing a Vmc demo?

I had to draw the fuel system, prop system, pressure system, landing gear system, and the electrical system up on a white board and explain them one by one. I was asked failure type questions for each system (except the pressure system). Tarp has it right - I was asked how much fuel is used by the heater per hour. I already had the line for the heater coming off the right tank in my diagram, so I wasn't asked which tank. I was asked where I can find the valves to add Nitrogen pressure to the hubs of the props. And if in a jam somewhere, can I add oxygen instead if Nitrogen isn't available? Lots of stuff like that.

Tanis is dead on when he says that you gotta know the systems. It's a biggie. Far more in depth than for my single engine commercial, although maybe it's a DE thing.

Lastly I had to do weight and balance stuff - one of my pax was extra big, which I assumed the DE did on purpose to see if I'd put him up front to lower Vmc, etc - and performance figures. Accelerate and Stop, Accelerate and Go, Single engine climb rates, and then the rest of the typical ones.

That was it. Lasted about 2 hours, with much of time being spent drawing those dang systems up on the board! I guess your may be longer since the DE will be asking all the other commercial questions as well...

Hope this helps!