Oral Prep for the Commercial Ride

Skydreamer2015

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Skydreamer2015
Hey everyone! What have some of you used to prepare for the oral portion of your commercial checkride? There isn't as much prep aids out there for the commercial as there was for the instrument so I was just seeing how you prepped for it. Thanks!
 
Know aircraft systems especially the gear and prop system, priveliges of a commercial pilot, then the rest of the stuff is basically the same as private.
 
Like Jordan said, know your systems. More than just what the POH says. Be able to draw the complete prop and landing gear systems. I was asked to sketch the prop control valve and describe what happens if each part breaks (springs, fly weights, piston). He asked if I had a nitrogen charge in my prop hub? If I did have it, what would it be used for? Deep details.

Understand common carriage and holding out.

Otherwise, not much new beyond what you already know.
 
Be able to draw the complete prop and landing gear systems. I was asked to sketch the prop control valve and describe what happens if each part breaks (springs, fly weights, piston). He asked if I had a nitrogen charge in my prop hub? If I did have it, what would it be used for? Deep details.
If that stuff helps you to understand what you're doing, great, but if an examiner asked me those questions I'd probably take a discontinuance and find another examiner to start over with. They're certainly not operationally-oriented questions, and as an instructor/examiner, I see enough pilots trying to treat malfunctions as mechanics or engineers instead of pilots that I think the negative training aspects are greater than any potential benefit.

It's definitely in your best interest to know prop malfunctions, for example, to the point of which ones the AFM checklists do or don't address, and what to do for the ones that aren't addressed. If you don't preflight springs, flyweights, pistons, or nitrogen charge, the specifics of those items aren't extremely relevant beyond what you should see when you test the system or how you deal with malfunctions.

Be able to identify the symptoms you will see, not the components that you can't. This will also make it easier to explain to mechanics what's wrong.

But maybe I'm just getting more cantankerous in my old age.
 
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Like Jordan said, know your systems. More than just what the POH says. Be able to draw the complete prop and landing gear systems. I was asked to sketch the prop control valve and describe what happens if each part breaks (springs, fly weights, piston). He asked if I had a nitrogen charge in my prop hub? If I did have it, what would it be used for? Deep details.

Understand common carriage and holding out.

Otherwise, not much new beyond what you already know.
I wasn't asked that much in detail but I had a picture of the prop system with counterweights, speeder springs, oil hub, etc and had to explain what each one did when I moved the prop control. I also had to explain, using the landing gear hydraulic schematic, how the gear worked. The examiner wasn't looking for A&P level knowledge but still wanted a pretty good idea of what actually goes on when you move the blue lever.
 
I was asked to sketch the prop control valve and describe what happens if each part breaks (springs, fly weights, piston).
"Declare emergency"

Do OTR drivers have to be able to diagram a diesel engine?
 
I wasn't asked that much in detail but I had a picture of the prop system with counterweights, speeder springs, oil hub, etc and had to explain what each one did when I moved the prop control. I also had to explain, using the landing gear hydraulic schematic, how the gear worked. The examiner wasn't looking for A&P level knowledge but still wanted a pretty good idea of what actually goes on when you move the blue lever.
Can anyone explain why that kind of depth is needed to fly commercially? You're not going to fix the damned thing...
 
Can anyone explain why that kind of depth is needed to fly commercially? You're not going to fix the damned thing...
Systems knowledge is important. The DPE is an A&P and AA pilot so he always put emphasis on systems. It's not a big deal. Just caused me to do a little more studying! I didn't mind it.
 
This is a nice simple description
http://www.mccauley.textron.com/von_klip_tip_cs_propeller.pdf

Print a couple pages and bring it with you just in case. I think the examiner just wanted to keep pushing me until I had to say "I don't know" - partly to see how I would react. I felt he was fair with me - and I passed so all is good.

For example, he asked "so, you lose engine oil pressure. what happens? engine might keep running for a few minutes - but what about the prop? what can you expect it to do? and why (to prove I wasn't guessing, but understood the system)"
 
For example, he asked "so, you lose engine oil pressure. what happens? engine might keep running for a few minutes - but what about the prop? what can you expect it to do? and why (to prove I wasn't guessing, but understood the system)"
That's pilot level knowledge...you have a cockpit indication, you know the results, and hopefully you showed him the appropriate checklist(s). No need to draw the system, and most airplanes built since the 1970s have had that information in the AFM if you need references.

On the other hand, "what would happen if the dome lost its nitrogen charge?" is something of a waste. What indication would you have in the cockpit? Probably a failed prop check. Do you have to be able to identify HOW the prop check failed? Yes. Do you know or care WHY it failed? No...You just need to get it fixed before flight.
 
To directly address the OP's original question, however, I would suggest being quite comfortable with how to use 91.213 to determine whether or not you can fly with a given piece of equipment inop.
 
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My commercial CFI was mostly a stick and rudder guy. Before the checkride, I paid another, much more technically oriented, CFI for an hour of mock oral time. It was money very well spent and highlighted my weak areas. And this was after I was thoroughly familiar with the ASA oral exam guide.
 
To directly address the OP's original question, however, I would suggest being quite comfortable with how to use 91.213 to determine whether or not you can fly with a given piece of equipment inop.

This. It's a hot button item for the FSDOs right now. Too many airplanes that aren't airworthy causing discontinued rides, is what I heard triggered it. There's also a good Advisory Circular on it.

I also liked the ASA Oral guide, but it's not comprehensive... it makes you think about other things that could be asked. I like the format.

One of my DPEs was a systems trainer. He likes systems. At the Commercial level he'll ask about failures and a generic system overview of how it all works and what you can do about it from the cockpit. At the CFI level, you'd best be ready to teach all that detail.

Commercial privs is always a hot button during the regulatory questions. You'll also plan a longish XC and then be asked bigger picture questions than a Private candidate about why you chose that route, airspace is always fair game, and probably a scenario that touches on weather, diversion, and maybe some off-loading of one passenger and loading another at an intermediate stop. In other words, an abbreviated long XC discussion about stuff you might see that's different than a typical private flight.

Speaking of Advisory Circulars, that's a topic that often gets little love in Private checkrides, but Commercial examiners might ask things that pulling out an AC might be an excellent way to answer them. Browse the AC catalog and print off some common ones or have them available on the iPad, whatever.

Know WHERE to find stuff in the FAR and AIM. Spend some time in each. If a question is really "out there" but you know it's covered in the AIM, say so, and that you'll look it up. Sometimes all they're looking for is that you know the topic is there, other times they're having you look it up to set up a scenario or question.

There's SO much information available from FAA, if you're well versed in what's out there in it all, and can flip to the generally right area and find it, that's often part of the "stretch" type questions in the Commercial ride. Mastery of knowing where to find stuff shows you really studied and it often helps the oral go very smoothly. The examiner can tell in five minutes if you've really put in the time with the books. That becomes more important and detailed at the CFI ride, but it never hurts at the Commercial ride.

One of my questions was an electrical system fault that required knowing exactly how the busses were separated on one aircraft. It was real-world enough that you needed to not be cold reading the electrical systems part of the AFM, but also had a feel of "looking for the practical answer from the cockpit and appropriate judgement" besides being about knowing that particular system.

Props are always seemingly on the list, too. Again, the examiner can tell if you really read and understood the prop system in only a couple of questions.

In aircraft with any kind of "interesting" systems, expect a question or two there, too. In the twin, I got a few questions about proper operation of the Janitrol heater in cold weather.

How do you use it? Are there limitations on using it? How much fuel does it burn per hour? Did you factor that into your fuel reserves for this flight? How do you reset it, if it overheats?"

These were all quick Q&A that took about as long as it took you to read them here.

But also expect scenarios.

Annnnd of course, whatver changes the new Commercial ACS brings as FAA retires the PTS this summer, supposedly.
 
Hey everyone! What have some of you used to prepare for the oral portion of your commercial checkride? There isn't as much prep aids out there for the commercial as there was for the instrument so I was just seeing how you prepped for it. Thanks!
I asked a the chief pilot at the flight school to run me through a simulated oral and as it turned out he was much tougher on me than the DPE.
 
You'll also plan a longish XC and then be asked bigger picture questions than a Private candidate about why you chose that route, airspace is always fair game, and probably a scenario that touches on weather, diversion, and maybe some off-loading of one passenger and loading another at an intermediate stop. In other words, an abbreviated long XC discussion about stuff you might see that's different than a typical private flight.

Will they let you know this in advance and you already have the XC planned, or does he give you the destination and you do this in front of him from scratch?
 
Will they let you know this in advance and you already have the XC planned, or does he give you the destination and you do this in front of him from scratch?

Most DPEs will give the destination to you beforehand but will want details on why you chose the route you did, and weather prep based on the day of, etc.
 
Just remember the option exists of telling the examiner you want to quit because he is asking hard questions that are making you feel uncomfortable
 
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