I think big helicopters with wheels can be safely taxied like airplanes, but not knowing I will have to defer to UH60andC-180 and Cam Tom 12 on that.

Regardless of weight, the hovering helicopter is just "blowing in the wind" as the Hippies used to say. It wants to drift downwind at the exact speed of the wind. If we bank or pitch the tip path plane (big round wing) into the wind to stop any drift, the tail boom immediately wants to weathervane with the relative wind. If we touch down while drifting with the wind, there is a tipping force that has to be dampened quickly with more bank or pitch of the tip path plane into the wind.

Helicopters pilots, like bull riders, have to be proactively and dynamically quick while hovering. They also have to consider wind as much as the pilot of a very light tailwheel airplane.

Helicopters respond to the elements much like airplanes much more when flying than when hovering. Flying begins at transitional lift when the big round wing encounters enough relative wind to produce enough pressure airspeed over the big round wing. This happens at very slow pressure airspeeds. It is around 12 kts for helicopters I have flown. With a helicopter, we are no longer hovering but are flying while at zero ground speed in a 12 kt wind. Things are good, even better than engine thrust only hover, so long as we are pointed into the wind so the tail boom can weathervane.

Wait! The big round wing doesn't care which way we are pointed. Yes, but the pilot does. The Wright brothers found out that putting the tail forward into the relative wind had dangerous control problems. At least they didn't face the pilot backwards.

When operating around helicopters, even in a light wind, we airplane pilots need realize that the helicopter pilot is more comfortable flying like he were in an airplane or hovering into the wind so that the big round wing is pitched forward and the tail can weathervane. The helicopter pilot will often manage the wind in such a way that he makes his final approach directly to the helipad directly into the wind. In this way he avoids the much more dangerous to himself and others hover taxi.

That is part of the reason good helicopter pilots land well away from all other aircraft and walk to the FBO, restaurant, or whatever.

Here's an example from the Salem, OR airport when a student lost control trying to taxi:

Couple times I thought a quick nose scratch would leave me looking like that. Nothing like doing all that stuff contact said with you knees while you tune a radio and try not to spill your coffee.

Is that Salem sample why I used to get asked where the helicopter museum was and I would have to say that I've never seen one. Now that was some time ago, but I still got a bit panicky when one of my younger grand daughters qualified for an Idaho Helitack Fire Crew.

Airplane guys are just jealous. Always trying to get that backcountry plane to fly slower but it just won't hover.[emoji1]

Hey Waterboy

Back in my teens there was an older pilot that flew an old Aeronca C-3 Guppy backwards from Palo Alto to the old San Jose, Ca. field.

My 1939 Piper J-5 - unfortunately "hovered" several times trying to get it through Chickaloon Pass while struggling to reach Anchorage

Tru stories - both of em.

Treim

Hey Waterboy

Back in my teens there was an older pilot that flew an old Aeronca C-3 Guppy backwards from Palo Alto to the old San Jose, Ca. field.

My 1939 Piper J-5 - unfortunately "hovered" several times trying to get it through Chickaloon Pass while struggling to reach Anchorage

Tru stories - both of em.

Trim

Trimtab wrote:Hey Waterboy

Back in my teens there was an older pilot that flew an old Aeronca C-3 Guppy backwards from Palo Alto to the old San Jose, Ca. field.

My 1939 Piper J-5 - unfortunately "hovered" several times trying to get it through Chickaloon Pass while struggling to reach Anchorage

Tru stories - both of em.

Trim

Winds can be fun. When I worked in Juneau Ak there was a guy who only flew his super cub when the wind blew over 30 knots. He would park it in the wind at 200 feet.

Interesting (I thought) video of a rookie learning to hover.

I've seen that video, it's pretty good.

Like Jim and Brett said, there's a lot going on aerodynamically during a hover that has to be countered by the pilot. Its fun in an unaugmemted helicopter.

Savannah-Tom wrote:Here's an example from the Salem, OR airport when a student lost control trying to taxi:

When did that happen? do you know what the name is of the instructor or was it just the student?

This is what a hovering helicopter wants to do when someone tries to fly one without any instruction!

This is several years old, the original which was much longer, was given to the FAA. An FAA inspector brought a copy to one of our briefings to share with the unit. We were told a family member filmed it. At the beginning "Boss" was waiting for his instructor, he became impatient and decided to get in and "just" start it, moments later he decided to get it light on the skids, that's when things went to he!!. At the end of the original, "Boss" walked over and kicked the wreckage. This version ends just before that happening. Luckily the only thing injured was the machine, his pride, and his bank account.

https://www.youtube.com/watch?v=WF11V4hdFIs

The Mattel Messerschmitt, Hughes 269 or TH-55, was the quickest control response trainer. Things happened much faster than Bells or especially the other Army trainer, the Hiller. Dynamic proactive control response on collective, cyclic, and especially anti-torque pedals is necessary on any helicopter but we had to walk the pedals much faster in the TH-55.

Like the Cub or any narrow geared tail dragger, it doesn't matter how much we move the pedals. It just matters that we move them proactively and dynamically. This guy was doing fairly well with the collective and cyclic, but he was being much too careful with the anti-torque pedals. Tenative control often means no control and this little guy can spin like a top if left to its own recognizance.

Geoffrey Thorpe wrote:Interesting (I thought) video of a rookie learning to hover.

Nice find, I can certainly relate to that at the moment especially when it finally clicks and your brain/muscle memory can put all inputs into one balanced motion.

Some balanced and some unbalanced. That's what makes it so exciting. Motorcycle throttle and anti-torque pedal movement is somewhat balanced with collective movement. But cyclic movement is not balanced with either collective or pedal movement. We end up patting our head while rubbing our tummy, like the side slip in a crosswind landing. Staying proactive and dynamic on all controls (twin rotor Chinooks excepted on collective) results in the appearance of balance.