I have noticed that Black Hawk helicopters have tires, but I have not seen one take off like a plane.
When would a helicopter need to use a running take off or landing?
When is it determined whether a helicopter gets skids or wheels?
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AOPA has a nice little blog post on the matter
Skid landing gear is simple and lighter weight, so it is the best choice for small helicopters as weight is always a consideration. Also, skid landing gear needs very little maintenance, but the drawback is that ground handling is more difficult.
And for wheels
On larger more powerful twin-engine helicopters weight is not as big of a concern and retractable wheels make sense. Wheels are nice because a helicopter can ground taxi (as opposed to hover taxi) around other aircraft and people without worrying about producing a high downwash. Retracting the gear also reduces drag, allowing for a higher cruise speed.
So skids are light and simple and wheels are convenient when you have the useful load and space.
This article also notes thats skids are preferred when parking on an non-level surface to prevent accidental rolling around and or sliding off the deck of a carrier.
The answer seems to be that they are chosen based on the mission profile of the helicopter as well as the size to some extent.
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1$\begingroup$ When would a helicopter need a running take off? $\endgroup$ – Muze the good Troll. Jun 25 '19 at 22:52
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4$\begingroup$ When it is over weight, high altitude, or hot weather. $\endgroup$ – Ron Beyer Jun 25 '19 at 23:15
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4$\begingroup$ The rotor's lift jumps when the rotor starts to get clear of its own downwash and is biting undisturbed air. It's called "translational lift". At about 20-30 kt. If you have wheels you can roll until you have translational lift and takeoff in conditions where you're too hot/high to hover in ground effect. If you have skids you have to try to get the machine sliding along on the skids. On grass not so difficult, but tougher on pavement. Performance and ground maneuvering wise, wheels are always better. But the wheels are single-point of surface contact and can be a problem on soft terrain. $\endgroup$ – John K Jun 25 '19 at 23:40
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$\begingroup$ And parking a helicopter with wheels is a lot more convenient. For a helicopter with skids you need to either attach wheels to the skids to make it roll or hoist the helicopter onto some kind of wheeled platform or cart. Both of which mean specialised equipment which of course isn't universally available as it often is specific to a type of helicopter (meaning the wheels for a UH-1 won't fit a Bo105 most likely). $\endgroup$ – jwenting Jun 26 '19 at 3:48
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1$\begingroup$ For embarked helicopters, wheels are the only practical way to maneuver on the flight deck. $\endgroup$ – AEhere supports Monica Jun 26 '19 at 11:20
