Checkride Horror Stories...or not

[350DRIVER]

Don't forget the 8710.

Speaking from personal experience now.

Makes for a crappy flight home.

Ya know what? Your CFI should be hung....


no excuses on this one-


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[350DRIVER]

I think i should take his cigarettes away for a week.

or....


Give the FAA a "very friendly" call and "reason" to 709 ride this guy... j/k


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[Snakum]

I think i should take his cigarettes away for a week.

Hey ... let's not get cruel.

If he got you ready in 40 hours, he obviously did his job well, and you've certainly been busting your butt, too. Did you do a lot of flight simming while training?

Best of luck to you Friday.

Minh

(I had 106 hours on the books when I took my ride, which doesn't include at least 30 hours flown before I started logging time in 1995. I'm kinda slow. )

 

[Movin' on up!]

Wire thickness

I busted my private checkride on the 2nd question.
Q: Why is the thickness of the wires from the alternators to the bus bar thicker than from the bus bar to electronic instruments in the airplane?

A: In case there is an electrical overload. The thinner wires will burn and protect the instruments and avoids causing a fire.
HUH? Yup, the examiner said that "as a private pilot I should know the airplane I am flying in the most intimate way." CFI and school's chief pilot protested vehemently, but I still failed and an ugly mark is in my record. Mechanic said that could be an answer, but that he had never is his 25 yrs as a mechanic heard that explanation.

 

[mattpilot]

@Movin on up

That is one bullshiat answer from the DPE. I would of called the FAA and recommended retraining for this gimp. To late now though, huh?

ANyhow, The wires got nothing to do with protecting the instruments. Thats what the Circuit breakers are there for. The thickness of the wires entirely depends on the load the wire will receive and is expected to carry. In any case, you would want a strong wire to PREVENT any burnout at all, and would also be stronger than the circuit breaker. I'm sure they have standards for that - ask a mechanic.

Why in the hell would you want to put a thinner wire anywhere and give it the opportunity to burn, and cause an electrical fire behind the firewall? HELLOOO?

 

[Jedi_Cheese]

"He didn't have me recover until 10 or 20 feet above the corn"

Are you serious?

What I've been told is that DEs expect you to recover on your own once you breach 500AGL...which is the minimum distance required from people, things, vessels, etc...

I know of a DE here that for emergency engine outs, he has you fly it all the way to the flare over a cornfield... He owns the cornfield tho

 

[Jedi_Cheese]

The DE specifically says that you shouldn't touch the throttle until he says that you can. He does an engine out early in the lesson and one near the very end (the one at the end is where he does the cornfield engine out).

He also tries to get you to bust the class C airspace too if you aren't careful (the core of the C is about 1-2 miles away from the airport you fly to).

Usually, I go to 200ft if I have the field made before recovering. I recover higher if I figure it's iffy.

 

[pilotman2105]

Don't forget the 8710.

Speaking from personal experience now.

Makes for a crappy flight home.

Check http://av-info.faa.gov/. In the respective PTS, there is a fairly comprehensive pre-checkride checklist.

The only thing that it is missing is "Sanity."

 

[pilotman2105]

I went over the checklist 40 times...somehow I just took for granted that I had the 8710..can't explain why I didn't confirm I had it.

Sh*t happens.

For my ASES rating, I had the DE screaming at me. It got so bad that I had to exercise the applicant's right to discontinue the checkride. You're gonna have your good moments and your bad. Just shrug them off and keep going.

 

[mattpilot]

The wires from the alternator to the bus bar are thicker because they carry a higher voltage than the wires from the bus bar to the instruments. Each instrument uses less voltage than the alternator puts out to the bus bar as a whole, thus the use of a thinner wire

Then I was right, woohoo.

Not quite - Its not voltage, but rather load - also known as "Current". And Load is measured in Ampere. Ampere = Voltage/Resistance (Ohm). When looking at the circuit breakers in the aircraft, you see a number on it. Thats the max amount of ampere that this particular circuitbreaker can take. Normal load for that circuit is 80% of whats written on it. If the load goes above whats written on the breaker, it trips and the entire circuit is protected.


Also, on a similar subject (not really, but its interesting none the less ), its not Voltage that kills you, but Ampere. As little as 0.75 Ampere can kill you. Thats not a lot you say, and you are quite correct. The average human body has a resistance of between 500k-800k Ohm when it is dry. WHen you are wet, it is much much muuuuuuuucccccchhh lower. Anyway, to do some math, if you have a resistance of 500k Ohm, and lets say a current of .75 Amp touches and kills you, the voltage will have to be roughly 375000 Volts.

On the other hand, if your wet, your resistance will roughly be 1000 OHM (i forgot, to be honest - its been a long time since i had the class ). So some math tells me, for a .75 amp current to kill me, it needs to have roughly 750 Volts.

Notice those are all milli second exposures. Longer exposures at reduced current can also have a fatal effect. Its like "cooking" you.

Anyway, sorry i got carried away - i just felt like sharing that at the moment

Good night all

 

[mattpilot]

btw gkrangers, where you flying at? The area you are describing sounds so much like Tulsa

 

[pilotman2105]

So did you scare the DE?

Just think that he was having a bad day and I was on the wrong end of it. This particular DE is known for being very moody. If you catch him on a moody day, you've failed. If not, then you've passed...

 

[Movin' on up!]

Wire thickness

I guess what really got me was that his answer wasn't all completely correct either. I had my instrument and commercial with him too and he was much better in those rides. I guess he was having a bad day and made sure some of us did too. The school and I never talked to the FAA in Spokane. They had a bad relationship with the school because of another checkride incident. An FAA examiner gave one of our studens a 2 day CFI checkride! It lasted from 8 am to 5 pm the next day. School complained and FAA looked into it. Determined it was unusual and uncommon and supposedly had management talk to the examiner. After that, things did not go well between all of us.

 

[mattpilot]

@moving on up

I fail to see how any bit of what the DPE said is correct. Maybe someone more experienced with electrical curcuits can enlighten my ignorant arse? Or at least confirm what i'm saying ? I think the mechanic only agreed by saying "that could be an answer", because he didn't want to look like a dumbarse. Afterall, DPE's are all knowing


Anyhow, again ... you would never want a thin wire that would/could burn out and cause an electrical fire. The DPE's answer is contradictory, by saying "thinner wires will burn .... and avoids causing a fire". If the wire will burn, it will also burn other wires and ruin a lot of stuff behind the firewall - making you even more screwed .

The thicker the wire, the better. The only thing preventing us from using TO THICK wires, is the resistance the thickness brings with it. If i remember correctly, if you double the radius of the wire, you quadruple the resistance(ohm). This would mean you would have to send a higher voltage through the wire, to get the same Ampere the instrument will require to function.