Deg. of motion

[Barannfin]

Hey I was just thinking about slope operations in the 22 and I got myself stumpted. What is the range of motion for the head on the r-22 is it 9deg. or 15? I can't remember.

And hey while were at it, how does that translate into slope landings? like maximum slope. And what are some other factors that you have to take into consideration?

[Nick Lappos]

The lateral slope angle limits are usually a bit more than the number of degrees of lateral cyclic from trimmed hover to the lateral stops. For example, if the stick is at 40% from the left stop in a hover, and the total lateral rigging is 12 degrees, the left upslope control is 40% of 12 or about 5 degrees, the right upslope control is about 7 degrees, so we'd expect that the right upslope allowable landing angle to be about 6 or 7 degrees, and the right slope angle to be about 8 or 9 degrees.

The extra bit of slope angle beyond the full control range is due to the skid/wheel friction and the moment capability of the rotorhead. These allow the last degree or two of slope to be held while against the stops.

Longitudinal slopes are sometimes limited by the rotor/fuselage contact angles, and the tail upslope angle can be limited by the fuselage ground contact propensity.

[SASless]

Nick....

It struck me as I read your post....you didn't mention tail rotor...ground contact popensity.....you speaking Commanche already? I can say ....tailboom...or tail fuselage ground contact never worried me as much as sticking that hi rpm buzz saw into something that would give rise to much consternation. Now for us real helicopter pilots.....(before anyone gets the entirely wrong idea.....by that I mean Chinook Pilots) we never worried about touching the tail end of the fuselage to the ground. Before we could stick the aft rotor blades into the ground we would almost get nose bleed from the altitude of the cockpit due to the angular difference and the height differential between the aft gear and the pilot's nose. Chinooks being the odd cat in the pack....we really were more concerned with hitting the nose during running takeoffs or aggressive departures than hitting anything else.

[GLSNightPilot]

Sticking the tail rotor into the ground on a slope usually isn't an issue, unless you're so foolish as to put your tail upslope. If you do that, you have no business flying there anyway.

[Nick Lappos]

Tail upslope phobia is like many helicopter urban legends. Folks who fly helos with low unprotected tail rotors must watch out, of course. However, the idea that any tail upslope in any helicopter should be forbidden really makes little sense.

With helos that have high tail rotors, and good ground clearance angles to the tail cone, tail upslope should be considered as a possible landing technique, if warrented.

[RW-1]

What a coincidence of conversation!

Sat I took a 22 over to an EAA fly in to give rides, had a blast.

When I came in I got a parking spot near the windsock away from the ultralights (don't want to blow them over, etc.)

My first setdown actually ended up with the tail upslope.

The slope itself as about 2-3 deg (beginner guess here), and before I set down I assured myself looking back (to me) that it wasn't going to rise up and hit my tail.

I actually found myself more worried that when I went to pick up later that I may unconsiously give enough aft cyclic to plant the tail rather than lift striaght up, but they ended up being unfounded. So if given a choice I would take level, but not afraid to set it down tail upslope if conditions warrent.

I did however do a walkaround of the area given and found I had room to set down skids just within the wind circle boundry of the windsock where it was level without worry to the mains for clearance and used that spot for the rest of the day.

BTW, I had a blast that day, for me racking up 2.4 in one day feels like 8. and i introduced 4-5 people into the world of rotorcraft flight, they really liked it as much as I did. :)