WDP: issues with pop up tools ?
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I tried to reproduce with WDP the example provided in the Korean AF BEM, Volume 5, 1 October 2005
(5.17.1 Sample Pop-Up Attack Computation) and I didn’t get the same data as the PDFAOD, distance (pullup target) , offset angle, TAS speed
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for WDP, the pull up point shouldn’t be on the target - IP axis because it involves to roll out and pull up in same time
it explains why we got the offset angle bigger and a distance action point ( here pull up point) / target smallerhowever, we dont’ process like this …
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@Falcas could you please check if the Offset angle is correctly calculated ?
to respect the key points following:
- climb & dive angle (20° & 15°)
- release height (2000ft)
- speed 500cas
- G 3.5
- Angle off 40
It is impossible to obtain an Offset Angle equal to 25.5°
after drawing a schematic on paper, I checked that the Offset Angle is lower than 25.5°, and I found 17°
AOD is correctly calculated : AOD = (release altitude/tan [dive angle]) - bomb range = 2000/tan (15 degrees) - 4902=2562ft
MAP distance = bomb range + tracking distance with :
Bomb range = 4902 feet
Tracking distance = 1.69 x GS x tracking time
MAP Distance = 1.69 x 500 x 5 = 4225ft ~ 0.7 nm
Vertical tracking distance = 513 x sin (15 degrees) x 1.69 x 5 = 1121 feet
Track point altitude = pickle altitude + vertical tracking distance = 2000 + 1121 = 3121 feet
Apex altitude = track point altitude + (dive angle x 50)
Apex altitude = 3121 feet + (15 x 50) = 3,137 + 750 = 3871 feet = Approximately 3,900 feetPull-down altitude = Apex altitude - (climb angle x 50) = 3871 - (20 x 50) = 2872 feet -> correct
Pop-to-pull-down distance = (Apex Altitude (AGL) x 60)/Climb Angle = 3871 x 60/20 = 11613~1.9nm