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PNR
David.Elzig8
Topic Author
David.Elzig8 created the topic: PNR
Hello,
looking for a bit of help on these two questions. Very similar. How is one supposed to find the fuel flow for safe endurance to calculate the PNR. was able to find the G/S home and out on whiz wheel, but still not enough information to calculate SE.
Cheers,
David
Please see examples below.
Given that the ECHO has 130gal of fuel on board at start-up for a charter flight.
The TAS is 175kt
The FPT is 260°M
The GAF wind is 100°T @ 30kt
and the variation is 6°E.
Find the time and distance to the PNR if the flight is to be conducted at 65% MCP.
Select one:
The time to the PNR is 102 minutes and the distance to the PNR is 325nm
The time to the PNR is 85 minutes and the distance to the PNR is 314nm
The time to the PNR is 92 minutes and the distance to the PNR is 314nm
The time to the PNR is 82 minutes and the distance to the PNR is 309nm
Given that the ECHO has 88gal of fuel on board at start-up for a charter flight.
The TAS is 185kt
The FPT is 300°M
GAF wind is 090°T @ 30kt
The variation is 15°E.
Find the time and distance to the PNR if the flight is to be conducted at 65% MCP
Select one:
PNR is 75 minutes and the distance to the PNR is 216nm
PNR is 70 minutes and the distance to the PNR is 196nm
PNR is 65 minutes and the distance to the PNR is 231nm
PNR is 60 minutes and the distance to the PNR is 206nm
So does that mean that I can not get these type of questions in the exam as they are not supplied in the DAY VFR Workbook, and only in the supplement I assume comes with your CPL textbook series?
Or is this something that needs to be memorized completely now?
You will still get PNR questions, but the examiner will include all associated data with the text of the question. I have used the Echo manual in the supplement because it is the kind of thing you would have to do in the real world. The exam will include all info you need for things like TAS and FUEL FLOWS in each individual question. You won't have to look up any tables etc.
I would like to clarify something although I know those data will be given in the exam. I am looking at page 16 and the FF for mix cleaned is 14 and mix full rich is 16.9. Where do you have the data for 28 gph?
Given that the ECHO has 88gal of fuel on board at start-up for a charter flight.
The TAS is 185kt
The FPT is 300°M
GAF wind is 090°T @ 30kt
The variation is 15°E.
Find the time and distance to the PNR if the flight is to be conducted at 65% MCP
In this explanation below. For SE you didn't divide it with 1.10, did you?
My work I have FR =21 gal --> SE = (88-3-21)/ 1.10 = 58 gal ---> 124 minutes. It is quite different to your calculate
Ground speed out = 205kt
Ground speed home = 162kt Safe endurance = 136.3min
Time to PNR = 136.3 x 162 ÷ 367 = 60.2 min (60min)
Distance to PNR = 60.2 min @ 205kt = 205.7nm (206nm)
The correct answer is: PNR is 60 minutes and the distance to the PNR is 206nm
