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CisseV t1_ix8mayl wrote

Helicopters generally operate with a fixed range of rotor RPM, lift generated is changed through pitch (collective) of the rotor blades. Weight does impact performance a lot, especially at hover. at higher weights and altitudes, hover might actually not be sustainable.

taking the Apache as a model, wikipedia gives us a weight of

Empty weight: 11,387 lb (5,165 kg)

Gross weight: 17,650 lb (8,006 kg)

Max takeoff weight: 23,000 lb (10,433 kg)

for gun ammo i've taken M789/M788 which ways around 340 grams per cartridge. x1200, which is maximum ammo capacity gives us 408 kilograms of weight in gun ammunition. which is a not insignificant percentage of the weight.

whilst in a hover, weight loss is generally slow because of fire rate (unless you jettison other external stores or fuel tanks), so collective change will be very slow, but will be needed if you dump all your ammo in one go from the same position in a hover.

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Wonderful_One5316 t1_ixa1p7e wrote

Does ammo play a part in your flight path and loadout?

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CisseV t1_ixa3cj1 wrote

More ammo means more weight, thus less range. For the Apache specifically, the internal ammo bay can be fitted with an auxiliary fuel tank. In order to extend range or loiter time.

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tim36272 t1_ixc5xc6 wrote

In addition to what the other poster said: it also impacts performance planning. The flight computer takes weight into account and will determine things like whether or not you can climb over that mountain and how fast you can climb.

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