To all CFI's: Stupidest student questions.

[jtrain609]

I've always thought they should work out some kind of clutch system for props. Rig up something similar to a car's AC compressor. The FAA would NEVER certify something like this though!

It exists, and is called a prop brake.

 

[Tommay85]

It exists, and is called a prop brake.

On a turbine though right?

 

[jtrain609]

On a turbine though right?

Yup, they were on ATR's.

 

[DPApilot]

Yup, they were on ATR's.

And Saabs. Dangerous. Very dangerous.

 

[HerrGruyere]

So on the ATR and the Saab, it would just hold the prop in place while the engine idled/ran at whatever speed?

Sounds unsafe.

 

[USMCmech]

So on the ATR and the Saab, it would just hold the prop in place while the engine idled/ran at whatever speed?

Sounds unsafe.

Helicopters do the same thing with their rotors.

 

[Ajax]

Not a question, but I once had a pair of students that were husband and wife. When we did their 3rd or 4th flight we flew over our local VOR so I pointed it out, it happened to be just a few blocks from their house. Each of them said more along the same lines that they thought it was some hippie's house.

 

[zmiller4]

So on the ATR and the Saab, it would just hold the prop in place while the engine idled/ran at whatever speed?

Sounds unsafe.

Not really "whatever" speed...there were limits on when you could engage it (both on the power you could develop with it engaged, and on the prop RPM you had to be below before engaging it on shutdown). Eagle's were all disabled when I was there because they were expensive to maintain, but it was part of the ATR design of being capable of operating in remote areas with bad facilities (you didn't have to shut down both engines).

 

[A150K]

Not a question, but I once had a pair of students that were husband and wife. When we did their 3rd or 4th flight we flew over our local VOR so I pointed it out, it happened to be just a few blocks from their house. Each of them said more along the same lines that they thought it was some hippie's house.

Well....

kinda looks like

to the untrained eye...

 

[JustinS]

And Saabs. Dangerous. Very dangerous.

As long as you don't stand near the prop it can't be that dangerous could it?

Our college had a pilot visit from Botswana visit. He told us the airline there uses one of the engines as an APU and use the prop brake to hold the prop still during turns on ATRs.

 

[p1l07m4n]

As long as you don't stand near the prop it can't be that dangerous could it?

Our college had a pilot visit from Botswana visit. He told us the airline there uses one of the engines as an APU and use the prop brake to hold the prop still during turns on ATRs.

That's got to be one expensive APU!

 

[JustinS]

That's got to be one expensive APU!

I doubt it's that bad. They use it mainly to provide Air Conditioning on the ground. I bet it's not much different fuel burn than an APU you'd find on an ERJ or something. Also in those countries. Generally, Jet A is cheaper than Avgas.

 

[Chief Captain]

I doubt it's that bad. They use it mainly to provide Air Conditioning on the ground. I bet it's not much different fuel burn than an APU you'd find on an ERJ or something. Also in those countries. Generally, Jet A is cheaper than Avgas.

This one too!

 

[JustinS]

This one too!

Well I don't know if you're saying my statement is false and calling me out or what you're saying. But it's defnitely true. That's why a lot of overseas aviation organizations are straying away from recip powered singles to turbine powered. Not only for MX reasons, but the Jet A is significantly cheaper than Avgas there... I've talked with these pilots first hand. I didn't pull that fact out of thin air...

 

[High_Alpha]

I brain farted on "Kilo" once and just told the tower I had information "Uhh, uh, uh....Kitty Cat".

Heard a new guy (in his defense, a non-aviation type) working a radio one day, reading back a grid coordinate, blanked on "Uniform," and ad-libbed "Eunuch." That's hard to live down.

 

[DPApilot]

I doubt it's that bad. They use it mainly to provide Air Conditioning on the ground. I bet it's not much different fuel burn than an APU you'd find on an ERJ or something. Also in those countries. Generally, Jet A is cheaper than Avgas.

It burns a heck of a lot more. At least, the Saab at idle burns more than a RJ APU if you want decent air conditioning.

 

[rd757]

Heard a new guy (in his defense, a non-aviation type) working a radio one day, reading back a grid coordinate, blanked on "Uniform," and ad-libbed "Eunuch." That's hard to live down.

Had a student use "Nevada" in front of our tailnumber when calling ground for taxi instructions. I had instructed him on several occasions that "the 'N' in the tailnumber wasn't needed in the US. Tower didn't let him live it down for the entire pattern lesson. "Skyhawk Nevada 123AB cleared for the option." Had the phonetic alphabet down perfect the next week.

 

[Champcar]

Had a student use "Nevada" in front of our tailnumber when calling ground for taxi instructions. I had instructed him on several occasions that "the 'N' in the tailnumber wasn't needed in the US. Tower didn't let him live it down for the entire pattern lesson. "Skyhawk Nevada 123AB cleared for the option." Had the phonetic alphabet down perfect the next week.

Love it when tower plays along.

 

[JustinS]

Love it when tower plays along.

That or when a student says something so wrong Tower refuses to give them any kind of a clearance until they say it right, because they're tired of putting up with student pilots.

 

[Dan208B]

Had a student ask if aerodynamic properties changed depending on whether it was night or day. Of course I said yes, and ran with a detailed explanation for about five minutes until I ran out of BS.

From a friend of mine that's older and avoids night flying just because - "Dark air doesn't support lift."