Some precautions but it has been done
ddurakovich said:
Anyone care to share their techniques of TO/Ldg on soft/rough fields with a TD RV?
Our glider field is pretty typical, old farm field, now grass, small peaks and valleys, occasional gopher holes (none that will swallow an RV, I hope!), 2500 feet long, 50' trees on the extended center-line at each end. Thanks!
Hard to say by your description; not all gopher holes are the same!
RV's only have 5x5 tires. That is the size of a C-152 nose gear. There is not a lot you can do about the tire size, since axial size dictates rim size, which dictates the tire. As long as your plane is not super nose heavy (weight on mains). Some folks put heavier engines on their plane. It makes sense to me, the lighter your plane, the better it will be on soft fields.
Over the years, changing 5x5 tires on my RV, I see difference brands have different tread cross section profile. Some have a squarer tread edge, basically wider, so pick the wider brand. Sorry I don't recall the brands.
Second I'd install the wheel pants higher up on the tire (with more rubber exposed) and cut larger gap around the tire opening. Many folks fit their wheel pants almost dragging on the ground and with Min gaps, fitting like a glove, to get max speed. No wheel pants may play rock havoc on the flaps & wing skin. If there is mud you will have issues with the pants, so consider putting in some internal bulkheads to keep the mud out.
It ain't no C-180, but you can fly off a farmer field. The good news is your take off run is pretty short, landing even shorter, so you can pick the best part of the strip to operate from.
The 50' trees is not a big deal, but again temp, weight, winds.........how tall and wet is the grass? Once in the air, climb rate is pretty outstanding.
Constant speed prop and more HP of course helps takeoff and landing performance, but mostly the c/s prop. The C/S prop helps takeoff but it also helps landing on the RV. RV's are pretty slick and the constant speed prop at idle provides more drag than a fixed pitch prop at idle, which actually might have a little thrust if idle is high.
If you look at Van's "numbers" you see very short numbers, as low as 300 feet and no more than 550-600 feet at max for gross wt w/ 160 HP. Their numbers do not say prop type, but assume constant speed. At light weight and 180 HP, takeoff/landing ground runs are very short. You have to realize RV's are ALL different. So it's hard to nail down one number, but RV's usually meet or exceed expected performance.
All RV's have reasonably strong gears but they are springy. The RV-8 seems to have the most rugged main gear in my opinion, it is flat spring, verse a round tapered "Whitman" spring gear the others models use. Being flat it tends to not bend back as much in soft dirt. Also when you put a passenger in a tandem, like the RV-8 or RV-4, the CG goes aft big time. That should help reduce tail tip-up/nose over potential, if your mains run into a BIG hole. This is all conjecture and wild gussing on my part, but I flew my RV-4 off of grass and some rough forestry mountain strips with out any problem.
RV's don't nose over unless they are landed off field in really soft rough stuff. As you probably know you can get a Trike or Taildragger gear on most RV models. Both gear configurations can be be fine on the dirt, but there is some controversy about the nose tire version digging in and causing flip. That is a different issue from the taildraggers. Taildraggers RV's have flipped on rare occasion, but often its as the result of off-field emergency landings on really soft/rough surfaces. I have seen many Cessna's flipped on their back.
