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Canuck15
31st Mar 2007, 14:42
Can some one pleasehelp with this PNR problem. Thanks in Advance

A flight is conducted from X to Z via Y . Route detailes are given below.
X---Y Dist 460 Trk 065 w/v 090/25
Y---Z Dist 710 Trk 030 w/v 240/30

Normal TAS 210 One engine failure TAS 170
FOB 7000 Liters

FF normal 840 lit/HR
FF one eng fail 570 lit/HR

In case of engine failure, calculate the max distance of PNR from Y so that the A/C can fly and safely land at Y with the remaining fuel if one engine fails on the return flight.

pipertommy
1st Apr 2007, 10:01
First as you would have to work out the g/s`s for homewards bound and outwards flights.Failed heading home!
Next you want to see how much fuel you burn against distance travelled.
For this take the g/s and divide it into the fuel flow.I got failed eng 570/143= 3.99kg/nm(heading home 210trk) norm i got 3.56kg/mn Add these (7.55kg/hr)to find consumption flying out on two and back on one!
From first part/leg of the flight you would have burned 2100 for 2.5hr flight so 7000-2100=4900kg left! you normally would be given a diversion and reserve to subtract which dose`nt seem to be here so i took a 45mins reserve to arrive back with?
This now gives you 4900-630=4270kg
Finally divide this by first part you worked out(7.55) so 4270/7.55=565nm for your answer.
I have to stress its a year since i did any of this,but it gives you a start.They didnt really cover it in the atpl brush up.But you never know;)
Sorry should have said they did cover it but its hardly ever used in the exams!!

Canuck15
1st Apr 2007, 16:01
thanks for the help.I'll try it your way and see if i can match your answer

once again any one welcome with a suggestion on this ...


regards

pipertommy
1st Apr 2007, 16:36
What is the answer?

DesiPilot
1st Apr 2007, 21:37
PiperTommy,

You were spot on. With reserve I get 572 nm from Y and without reserve I get 656 nm from Y. (I didn't round up or down the time).

Canuck15
2nd Apr 2007, 06:03
Hey guys

thanks for the effort .


I got 589 NM
and a time of 2.5 hours .

I am gonna run thru it one more time to see if I screwed up some where..

Canuck15
2nd Apr 2007, 06:23
Hey pipertommy

Thanks ...now I got it right

DPNR 654 NM

TPNR 2H 46 M .


have a good one

Canuck15
2nd Apr 2007, 06:49
Hey Guys
I am pulling teeth trying this ..PLEASE HELP
A flight is conducted from A to Y via X . I n the event of a return flight due to weather consideration the A/c will be diverted to Z.
Flight Details FOB 3000 LBS
Dist Trk W/V Normal TAS Reduced TAS Nor F/C Red F/C
A to X 465 NM 040 150/30 275 240 550LB/HR 390LB/HR
X to Y 775 NM 140 300/35 275 240
Y to Z 350 NM 250 290/15 275 240


Calculate the time and distance to PNR in the event of one engine failure at PNR.

DesiPilot
2nd Apr 2007, 08:53
Canuck,

Same as last one except this time you are going to Z with few exceptions.

A-X normal GS Out
X-PNR Normal GS Out

PNR-X E/F GS Home
X-Z E/F GS home

Canuck15
2nd Apr 2007, 09:26
Hi Desipilot
thanks for the help. By the way is Z to even considered in this because the question is still asking for the DPNR incase of engine failure ...

confused

neilia
2nd Apr 2007, 10:29
Where's the question from? It looks more complex than any of the examples I came across for JAR.

Canuck15
2nd Apr 2007, 16:17
this question is similar to what you get on the Indian navigation exam for the ATPL.

I need some one to solve this ...i have not been able to yet ...

regards

DesiPilot
2nd Apr 2007, 20:07
Hey Guys
I am pulling teeth trying this ..PLEASE HELP
A flight is conducted from A to Y via X . I n the event of a return flight due to weather consideration the A/c will be diverted to Z.
Flight Details FOB 3000 LBS
Dist Trk W/V Normal TAS Reduced TAS Nor F/C Red F/C
A to X 465 NM 040 150/30 275 240 550LB/HR 390LB/HR
X to Y 775 NM 140 300/35 275 240
Y to Z 350 NM 250 290/15 275 240
Calculate the time and distance to PNR in the event of one engine failure at PNR.

Kanuck, I think you copied your question wrong it should have been
A to X 465 NM 040 150/30 275 240 550LB/HR 390LB/HR
X to Y 775 NM 140 300/35 275 240
X to Z 350 NM 250 290/15 275 240

Solution:

A-X Normal TAS: Dist 465, GSO 284, FC 550 therefore F Used= 900.52 lbs

X-Z EF TAS: Dist 350, GSO 228, FC 390 therefore F Used= 598.68 lbs

Total Fuel used= 1499

Available fuel= 3000-1499= 1501 lbs ....................... (1)


X-Y Normal TAS: Dist 775 GSO 308, FC 550 therefore F Used= 1384 lbs

Y-X EF TAS: Dist 775 GSH 207, FC 390 therefore F Used= 1460 lbs

Total fuel used= 2844 lbs ................................ (2)

From (2)
when fuel used is 2844 lbs DPNR is 775 nm
if fuel used was 1 lbs DPNR will be 775/2844 nm

Therefore from (1)
when fuel used is 1501 lbs, DPNR = 775/2844 * 1501= 409 nm

Hence the DPNR from A = Dist AX+ Dist X-DPNR= 465+409 = 874 nms

Now if you really want to pass your Indian ATPL exam please get some coaching from one of the instructors. These are the basic questions if you are struggling with these you will have hell of a time with DMP, Lat Nut, Flight Planning, Moon rise and other Navigation questions.

neilia
2nd Apr 2007, 21:56
The reason I queried this is that the question as reported doesn't appear specific enough to answer. Does the engine failure at PNR require you to fly to Z or to A? It's a nonsense. I saw nothing like this in JAR. Is it an actual Indian question or is it something created by a school?

Canuck15
3rd Apr 2007, 05:30
Hey Desipilot


first of all thanks a lot for your help ...I dont have any problems in the other subjects ...I would love to take some coaching classes but due to the nature of my work i cant sit in classes in India for 6 weeks ...BTW I am writing the composite. wish you the best .

DesiPilot
3rd Apr 2007, 07:05
Neilia,
This is not a non-sense question or created by school. I took the exams (Indian ATPL) in July last year and I saw similar question in my exam paper. This question is in Indian DGCA ATPL question bank. Sometime they ask similar question in the CPL exams.
Canuck,
Take a look at this http://www.indianpilots.com/forum/viewtopic.php?t=1226
Goodluck with your exams.