What's a TRU?

[Fly4Pay]

Woah. How? I thought CHA was closed for diverts? At least, that's what I saw in the NOTAMs the other day (and every other time I've flown in there).

It was, for quite a while. Just re-opened a couple of weeks ago.


And we packed it full last Thurs when a BIG line of TSTMS associated with Humberto rolled through during the busy afternoon-evening hours.

 

[CameronF]

Correct.
An inverter converts D/C to A/C.

The red line above represents D/C, and is converted into A/C which is the full sine wave of the blue line. Remember D/C is direct current, and A/C is alternating current. So when you see a sine wave like the blue line, it is alternating, usually at 60 Hz in the USA. Some countries use 50 Hz.

A simple inverter:

Here the D/C circuit starts where the + symbol is, goes through the transistors, and into the coil. This generates a magnetic field. An iron core separates the D/C coil, from the A/C coil. The A/C coil is energized by the magnetic field and is converted to A/C where it shows output.

It can get pretty complicated when you have 3 phases, and multiple transistors. This is the principle behind variable speed motors, like some home Air conditioning blower motors. You can vary the speed of the motor by changing the frequency of the sine wave. This technology is used in commercial and industrial buildings to control motor speed of pumps and fans, saving money on electricity bills.

Wow thats pretty complex it seems. How much of that is actually required to be explained in an interview?

 

[Tuckster]

Are you really expected to know these things on the interview Q & A ??

I feel prety good on the ATP stuff but some of the questions I've seen on the gouges seem to be specific to a particular airplane !!!! I'm considering appling to Pinnacle but guess I need more studying. I heard they have a few questions on RNAV equipment as well.

 

[MattB]

Not on the QnA at piedmont, but know what an inverter is on the written and then there are several 'TRU' questions on the take home study.

 

[avi8tor]

A rectifier converts AC to DC (remember rectifier wrecks AC) an inverter converts DC to AC.

 

[n57flyguy]

I think it's on the Pinnacle written test, too. CRJ has 5. I think the question actually asks how many are on the plane.

Just in general, what are they used for on the aircraft?

 

[kellwolf]

TRUs convert the AC electrical power to DC power on the a/c. They're located in the nose if they ask that, too.

As far as CHA, our 10-7 pages don't even have the ramp control gates in MSP properly labeled, and we just got new pages a few weeks ago. I'm betting we won't get the updated 10-7s for CHA for about a year.....