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Zahid_Muqaddam
10th Mar 2010, 16:50
Can anyone tell me how to solve this numerical to get the answer "C"

If a TOD of 800m is calculated at sea level, on a level, dry runway, with
standard conditions and with no wind, what would the TOD be for the conditions listed below?
Airfield elevation: 2000 ft
QNH: 1013.25 mb
Temperature: 21oC
Wind: 5 kts tailwind
Dry runway with a 2% up slope
(Assuming: ±20m/100 ft elevation, +10m/1 kt of reported tailwind, ±5m/1oC
ISA deviation and the standard slope adjustments)

A – 836 m
B – 940 m
C – 1034 m
D – 1095 m

Ans: C

ei-flyer
10th Mar 2010, 18:25
Based on the values given, none of the 'answers' are correct.

The adjustment for airfield elevation alone would nudge the TODR up to 1,200, then the rest of the variables are all negative, i.e. require a further increase in TODR... Tailwind, higher than ISA temp, upslope etc...

Wouldn't worry about it too much, there's a definite error here. :ok:

Keith.Williams.
10th Mar 2010, 18:56
TOD is standard condictions................................................8 00m
Correction for 2000 ft elevation........................................+ 400m
Correction for OAT 21 deg C (ISA + 10)...........................+ 50m
Correction for 5 kt tailwind............................................. + 50m
............................................................ ...Total .........= 1300 m

Correction for 2% upslope (x 1.1) gives 1300m x 1.1 = 1430 m

Is your onption of 1034m a mis type of 1430m?