Helicopter Jumps

Most skydivers—even if they’ve never had a flying lesson—generally have quite a good understanding of airplanes. After several hundred (or thousand) takeoffs and rides to altitude, jumpers tend to pick up a fair amount of knowledge as if through osmosis. However, helicopters are fairly uncommon around drop zones. Even fixed-wing pilots who are skydivers don’t fully understand how they work, and the average skydiver understands them even less. Since only a handful of skydivers also pilot helicopters and since only a few helicopter pilots have experience flying jumpers, educational resources are scarce and misconceptions are abundant.

Along with making sure to get a thorough pilot briefing before jumping from an unfamiliar helicopter, jumpers should review the following few tips to help make helicopter jumps safer for everyone:

First, never walk behind a helicopter. When the pilot briefs you to approach from the front when loading, it is not just so that he can see you; he wants to keep you away from the tail rotor. The tail rotor is small, spins about twice as quickly as the main rotor and is pretty much invisible when running. If someone comes into contact with a tail rotor, he won’t come away from it with just an injury... it’s invariably fatal.

Interestingly, engine failure is less of a concern with helicopters than with planes. Yes, when the engine of any aircraft stops making noise, it gets the immediate attention of its pilot (and passengers!). But while a plane needs a large, flat area in which to land, a helicopter can autorotate and glide down without engine power. Given some speed or 400 to 500 feet of altitude, a helicopter pilot can put his craft down in an area the size of a few tennis courts as long as it’s within his 45-degree viewing angle–and it doesn’t really require “Air Wolf” pilot skills to do so.

The loss of the tail rotor in flight is much more serious than engine failure. The side a standard tail rotor is mounted on depends on which direction the main rotor turns. (As a rule of thumb, American-made helicopters’ main rotors turn counterclockwise, whereas French helicopters’ main rotors turn clockwise; the tail rotor is then on the side that counteracts the torque effect.) However, you can forget this short physics lesson and simply remember that you need to be most cautious on the side of the helicopter that has the tail rotor. You’ll be flying doors-off on heli jumps, and loose cameras, clipboards and headsets have taken helicopters out of the sky when they hit the tail rotor. So take great heed when your helicopter pilot tells you to not hang anything outside of the helicopter during flight. This is also the reason why most pilots prefer that jumpers don’t stand on the landing skid on the tail-rotor side before exit.

Helicopters rarely come to a stationary hover when jumpers exit. It is possible for the pilot to perform this out-of-ground-effect (OGE) hover, but it is highly unusual. Usually, the helicopter will slow to around 40 to 60 knots for exits. There are many reasons helicopter pilots do not perform OGE hovers for jumpers:

• Helicopters are much more efficient at speeds of 20 knots and higher.
• OGE hovering uses a lot of fuel and requires substantially more power. (The helicopter may not be able to OGE hover at jump altitude.)
• Helicopters can more easily become unstable in OGE hover.
• Pilots can encounter a vortex ring state, which can occur when the rotors sink into turbulent air, causing an excessive descent rate.

Therefore, expect the helicopter to have some forward speed when you exit. As you exit, do not push off. This is most important when jumping from a smaller and lighter helicopter such as the Robinson R44 as opposed to a larger helicopter such as the Bell 412.

Photo by Michael Romanek

When exiting, jumpers occasionally encounter snag points on the skids, usually the attachment point for the ground-handling wheels (the mechanism to which the ground crew will attach wheels to the skids to move the helicopter on the ground). On most skid-type helicopters, this attachment point is located either inboard or outboard near the back area of the skids about 10-18 inches from the end. Oftentimes, jumpers can’t see this mechanism as they’re climbing out, but it can easily become a snag point for gloves or chest straps, particularly when jumpers climb down for the ubiquitous “look at me I’m hanging from a helicopter” photo or video.

It makes sense to ask the pilot during the pre-jump briefing if there is anything specific you should know about his particular aircraft. Different models of helicopters have their own design quirks that may affect skydivers who are climbing out. For example, the Robinson R44 has a small fuel-inspection drain button that is located only a few inches aft of the left rear door and squirts out aviation fuel if pressed.

Most helicopter exits occur between 4,000 and 5,000 feet above the ground. With the new experience of exiting at sub-terminal speed into “mushy” air, it is easy to lose track of altitude. This is particularly true if you left as part of a pair or in a group of three: By the time you realize you need some separation prior to deployment, you might already be down to 2,000 feet! There have been plenty of cases of jumpers experiencing dual deployments on helicopter jumps due to their automatic activation devices initiating reserve deployments as the main canopies were inflating, so be sure to stay on top of your altitude.

Helicopter jumps can be fun and novel, but it’s important to remember that they are very different from jumps from other types of aircraft. Make sure that you understand some of the basics of how helicopters work and get a thorough pilot briefing so your experience can be as safe as possible for everyone.

—Michael Romanek | USPA #196626
Federal Aviation Administration and European Aviation Safety Agency Private Helicopter Pilot
London, England