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jhthung
7th Aug 2015, 13:16
So recently, I sat the exam, and unfortunately I failed by 4%, literally like one question... Anyways, apparently ASL has introduced so many box questions into the all exams nowadays. I had 5 box questions for nav, and 6-7 for performance, one of my friends got half of the exam...

And I got a weird CP question that I haven't seen before in any of my notes and practice paper including AFT and Rob Avery.

I was given the departure and destination point, and the question asked me that what the ENGINE 1-iNOP CP for another two given places will be. So basically, I got to go to my destination and divert to the other 2 places with one engine out.
The flight level, wind condition and TAS are also given for normal and abnormal operation.

Is that anyone have any ideas how to do this?

404 Titan
7th Aug 2015, 13:57
jhthung

I was given the departure and destination point, and the question asked me that what the ENGINE 1-iNOP CP for another two given places will be. So basically, I got to go to my destination and divert to the other 2 places with one engine out.

The flight level, wind condition and TAS are also given for normal and abnormal operation.

Since when? There is a thing called “Enroute Alternates”. There is also a thing called “1ENGCP” to and Enroute Alternate. Whoever told you had to fly to an Enroute Alternate via the destination doesn’t know what they are talking about.

hoss
7th Aug 2015, 22:05
Take for example ML-CS with SY and BN as your enroute alternates.

Draw a straight line between SY and BN, find the halfway point, draw a line 90 degrees from the halfway point back towards your ML-CS track and you have your nil wind CP/ETP. Allow for wind (bit convoluted/haven't been there for a while) but in a nutshell CP will move into wind, so assuming a south westerly wind and find the answer south of this point.

Exam technique- prove your answer with whizz wheel (distance, speed, wind, time)

Cheers hoss

jhthung
8th Aug 2015, 00:36
Take for example ML-CS with SY and BN as your enroute alternates.

Draw a straight line between SY and BN, find the halfway point, draw a line 90 degrees from the halfway point back towards your ML-CS track and you have your nil wind CP/ETP. Allow for wind (bit convoluted/haven't been there for a while) but in a nutshell CP will move into wind, so assuming a south westerly wind and find the answer south of this point.

Exam technique- prove your answer with whizz wheel (distance, speed, wind, time)

Cheers hoss

I did the exact same thing, but I got it wrong... What wind should I use for moving the CP, normal or 1-inop?

drpixie
8th Aug 2015, 01:44
What wind should I use for moving the CP, normal or 1-inop?

When in doubt, invoke logic - for that part of the flight, would you be normal ops, or 1-inop?

The whole point of Nav and FPL is the see if the candidate can solve problems, problems that you might not have seen before. After all, you are asking for a licence that lets you be in charge of an airliner :ooh: (Lucky for students, most courses focus on lots of known problems.)

If your technique is memorise lots of situations and formulae, then you'd best add some logic to your repertoire.

hoss
8th Aug 2015, 03:01
Use the OEI profile in your case(exam). Again, prove that the time from this point is equal. Unfortunately, it will require some plotting and two sets of ground speeds and distances.

Taking a guess, I would be looking for a position up to 50nm south of the nil wind ETP on average. Don't forget to use the wind at your drift down ceiling. Stretching the memory, but if it's a 727 and they give you a GPF just use FL235. It might sound rough but it should be close enough.

Sorry I can't be more detailed I'm out building a fence.

Cheers, hoss