Helicopter payloads?

Question

What are the rules on utility helicopter payloads? Do they have increased gross weight or do they have to be restricted to normal gross weight even though they can lift significantly more?

For instance, when they lift lumber.

Answer 1

They all have different payloads.

some lifting helos:

Ch-47 chinook: about 33,000lbs.

Ch-53: about 20,000lbs.

UH-60: about 9,000lbs.

Answer 2

Helicopters tend to have two gross weights: one for internal loads (loads supported by the skids) and a higher one for external (jettisionable) loads that won't stress the skids.  the skids tend to be a limit because of crash-worthiness restrictions.

Answer 3

Thats a good question and i think it depends on the size of the copter.http://en.wikipedia.org/wiki/Tiltrotor

Answer 4

you take the maximum takeoff weight for expected landing altitude and outer air tempeture /value given in the flight manual/

then you deduct fuel necessary to get there plus necessary safety fuel

then you deduct the startup and taxi fuel

then you deduct crew and equipment of the crew weight

then deduct empty weight of the helicopter.

what is left is your maximum payload.

the more cargo you want to take, the less fuel you can carry /the further you fly the less cargo you are able to transport/

some helicopters have different MTOWs for different tasks, like the Mi 24 which actually has the MTOW of10.5 tonnes normally while 11.5 tonnes for a ferry flight with 4 outer tanks /the one additional tonne is approx weight of the two /outer stores/ tanks each having some 450 liters of fuel plus a dead weight.

with increased MTOW usually comes some kind of restriction to the Gload permissible, maneuvers flown etc.

Anyway Mi24 /and mi17 as well/ is rather overdimensed in its structure, while the western helicopters approach the critical torque closer. the MTOW is a definite value and noone seriously flying should disregard it.

more than that there are obvious limitations to the cargo, like maximum internal cargo, maximum suspended cargo load, maximum winch loading etc.

some helicopters are certified in several performance categories, where one of the categories enables the helicopter to continue climb during all the takeoff procedure <this is rough, not a citation> which is called cat A. the category is limited in the manual by certain weight value again, which is actually a MTOW in the cat. A configuration.

that is, when you want to fly over a large city, where only cat. A helicopters are permitted to fly, you can have the TOW of the helicopter maximum <value> while when you are lumbering with the very same helicopter, and dont mind the forced landing in the emergency, you can carry heavier loads, up to the MTOW, following the calculation at the beggining.

another example:

firefighting

you have virtual Jetranger, weighting 2 tonnes empty with one pilot. you have a refuelling place in the vicinity of the firesite, so you dont need a lot of fuel, lets say fuel for 60 minutes flight which would allow you with some 15-20 drops -> 300 liters equalling +-250 kilograms

Now your TOW weight should not exceed 2700kilograms /given by the virtual jetranger manual for the given locality and temperature/. this gives you maximum water capacity 450 kilograms=liters at the first drop, and this value increases as your fuel gets consumed, to the 450 + 200 kilograms/equaling 250 liters of consumed fuel per hour/. so at the final run you would be able to carry 650 liters of water to drop. Got it?