contactflying wrote:Airplanes, with dynamic neutral stability, don't have to be acrobatic to safely be stalled or spun or even out of control for a bit. Helicopters will destroy themselves when allowed to go out of control a bit. You can't even scratch your nose with the cyclic hand. Don't try a settling with power recovery technique that allows the helicopter to fall. Don't zero the airspeed with a tailwind. Even when we have to start an approach downwind, we can come about before zeroing the airspeed. Wind management is critical. Dropping or picking up a troop from a hover can be accomplished parallel to a ridge with the tip path plane tipped into the crosswind component. The same with working next to buildings or landing on the medevac helipad of a hospital.

I agree. Never trust the wind as mentioned. If the wind shears it can end badly. Especially at high DA as you wrote above.

In Arizona it’s amazing how many micro climates there are locally. Never trust the windsock! Most helicopters LD/max = “57 knots IAS”, I keep LD/max IAS in my hip pocket. Flying in air we can’t generally see the transmission of energy. There is little indication visually to alert an inexperienced helicopter pilot of diminishing stability. Although, physically the helicopter will quickly warn. In contrast, let’s say surfing a wave, we can see the energy and predict the movement. Sailing we can see the ripples and waves. The sails and rigging have telltales. Helicopter pilots need to evaluate the indirect values of their ship and weather, which takes time. And good instruction.

8GCBC wrote:In Arizona it’s amazing how many micro climates there are locally. Never trust the windsock!

Surprises can be found anywhere, and micro climates abound. T31 (Aerocountry in McKinney, TX) used to have 3 windsocks (north end, south end , and in the middle of the runway), and there would be many days where the windsocks on the opposite ends indicated opposite winds, with the "tie-breaker" windsock in the middle of the runway indicating 90º crosswind. Landing there could be "sporty" at times!

contactflying wrote:There have been some tail booms chopped off by the main rotor in several single rotor helicopters lately. I hope we are not over practicing rolling out or vortex ring state or what we called settling with power in the Army.

Vortex ring state and settling with power are actually two separate states of flight though they can be related, and we train for each and very differently. Settling with power, the airflow is not recirculating, you simply do not have out of ground effect hover capability and have flown past the helicopter’s ability to produce more lift than its mass. Usually encountered at altitude, or when the wind you departed into has disappeared, or very commonly in down flowing air in the mountains. Vortex of course is when the rotor disc starts reprocessing its own downwash, usually by descending into it with power applied at greater than 300fpm descent. So settling with power is often the recipe for vortex, but vortex isn’t established until the airflow recirculates, at which point settling with power is over and vortex has begun. Nearly all settling with power events don’t end in vortex ring state, though the risk presents.

There is no risk to training vortex, it’s a lot safer than an auto, as long as the training pilot knows not to over-control the aircraft. It seems gross over-controlling caused the recent Robinson tail chop, a degree of over-control that can be likened to kicking the rudder off a fixed wing with repeated full deflection inputs at speed. It was an extremely low time rotary training pilot who was a transitioned fixed wing pilot.

Thanks, Ardent. When I left the Army in 83 I had never heard of vortex ring state. I had one day training on long line in a Huey, but we certainly avoided getting into our own disturbed air out of ground effect. If forward cyclic didn't get us to quit settling, we punched off the load. Settling with power was used for very slow (5 min short final) approaches into 14,000 LZs on Pikes Peak during Army Mountain Flying School at Ft. Carson. We used a TOL card to figure what torque would be required for a 3' hover in the LZ, set that torque on short final, and never touched the collective until majic hover in the LZ. We zeroed the airspeed. If we settled, we moved the cyclic forward just a bit. If we moved up on the approach angle, we moved the cyclic around in circles until back on glide angel.

We didn't do much sling loads with OH6-A, but I always preferred the integrity and balance of the articulated rotor verses the semi-rigid. Hughes, Sikorski, and the French made good helicopters. Bell made good simpler helicopters, but the rotors were never in really good balance. Bell said 120 knots in Huey and we were very comfortable with 90.

Yep I hear you on 90kts, I’ve flown the original blades on the 205 / UH-1 (-13), and 100kts is cruise plain and simple. If you try and push faster you just shake and burn more fuel. Most have the 212 blades these days and will fly faster now.

The UH-1 / 205 (civvy variant) is a fantastic machine for longline, and we use them extensively up here on fires in particular, much better than the 212 / twin Huey that has largely replaced it. They just added weight and questionably engineered complexity with the second engine.

These days the AS350B3 / B3E / H125 (the machine that landed on top of Everest) has a strong case for competing as a water bucketing machine with the UH-1. It lifts 3/4s as much water burning half the fuel, is much much cheaper to operate and requires far less maintenance, and it flies the bucket faster so it delivers comparable water often. The 205 is more comfortable to longline from however.

14,000 is up there for sure, and keeping the machine sneaking along ahead of translational lift, and into wind and in the upflow, remain the golden rules of high altitude landings. The preferred recovery from vortex should you enter it is the power pedal and cross control (popularized and self named by Vuichard). You use your tail rotor thrust and drift to help push you out of the recirculating down flowing air. Recovery is remarkably quick compared to other techniques.