As previously noted, my primary flight training was conducted in the TH-55A (Hughes 300) trainer. The helicopter itself is not very inspiring and I had to overcome my doubts about both it and my capability to fly it.
As you can see it is basically a bubble on skids with a rotor attached, but it is actually a fairly rugged if not very basic aircraft. An altimeter, airspeed indicator, Vacuum gauge and tachometer are the instruments. The turn and slip indicator was a 2-inch piece of yarn on a straightened paperclip mounted on the center-line of the canopy at eye level. Door were optional, in cold weather we generally opted for 1 door on and one off as even at 40 degrees Fahrenheit it was better to be cold than not to have fresh air in the cockpit.
Another note is that this little bird is little, it was not designed for someone 6 foot 3 inches tall. My flight helmet rested on the back of the bubble and the vibration was not conducive to my control touch. Lucky for me the back of the helmet has Velcro loop attached for when I'd need to attach an NVG battery pack later in training and I was able to attach a large piece of 1/8 in foam rubber to act as a pad between my helmet and the bubble.
One of the first orders of business is learning how to hover. The best way I can describe this task is to take a straw broom (The old fashion kind, wooden stick and straw and heavy) hold it vertical bristles up, then try to balance it in the palm of your hand. You'll find it is easy to do for 5 or 10 seconds then it starts to wobble, then you overcorrect and then eventually it succumbs to gravity and hits the ground. This is pretty much how it feels to try and learn to hover. For 1 thing you are doing a minimum of four control movements at the same time,
You have the cyclic pitch control (The Stick) in your right hand. At a hover, it is movement left and right, forward and back. Pretty simple in theory. Next you have the pedals, these allow you to pivot around the axis of the main rotor and you use this to point the aircraft the direction you intend to go. This is kinda a nominal idea initially as the aircraft seems to have other ideas. Left pedal, increases pitch on the tail rotor turning the nose to the left, right pedal decreases pitch on the tail rotor and you turn right. Seems pretty simple, then you take into effect that more pitch on the rotor requires more engine power, if you don't add more power, besides turning left you will also descend as you are using more power. Conversely, by using right pedal, if you don't reduce power, you'll initiate a climb. One thing I'll also note here, is that the pedals are cable connected to the swashplate of the tail rotor and it is a direct link connection. This means that when there is drag induced to the tail rotor, if causes feedback on the left pedal requiring you to keep pressure upon it to hold your position. If you relaxed your left foot, the helicopter would automatically start turning right as the tail rotor always wanted to have the blade at flat pitch to eliminate drag. This also meant for all intents and purposes, that you could take your fight foot off the right pedal as the feedback provided all the right pedal pressure you ever needed, I was chided more than one by my instructor to get my right foot back on the pedal after I'd take it off the pedal to relax a sore knee.
The last two controls are combined. The collective pitch control (Up and Down and airspeed control) is held in you left hand. With it is a twist grip throttle control much akin to that of a motorcycle, just in the other hand. As you would pull up on the collective, you also in synchrony twisted the throttle away from you in an overhand motion. When you lowered the collective you relaxed the throttle. The goal was to maintain appropriate rotor RPM that was indicated by a secondary needle on the tachometer, the other indicating the engine RPM which I seem to remember would generally be about 2650 RPM when flying.
So I hope this clarifies a tad bit how operating this device is a balancing act. You are trying to convince this thing to 1. Defy gravity. 2. Defy wind (Oh my how clam days were appreciated.) and 3. Defy your own attempts to kill yourself and your instructor.
Hover practice was done is large fields throughout southeastern Alabama. Farmers would rent these fields to the Army and keep them free of major debris and allow things like a hover marker to be placed in the field. (An old tire with a reflector in the middle in the center of the field.) Hovering requires you to have a relaxed control touch and mostly practice relaxing while holding your life in your hands. Since most Warrant Officer Candidates are generally spring loaded to the Gee Whiz position, this takes some effort. Yes, it requires effort to relax when learning to fly. Generally, it talks about 3 to 5 hours of practice to get the basics of hovering down. Me, it took a bit more I believe.
It was a nice day, sunny and 40s or so, when Mr. Rhoads took me to this familiar 150-acre field we'd been spending an hour or so a day in for most the week, He was less than impressed with my skills at hover and was determined that this was the day that I would figure it out. It was. We were at a 3-foot hover facing due south (180 heading on your compass) and the tire marker I mentioned was in front of the nose of the aircraft. We did the normal 3-way transfer of controls (Mr. Rhoads said "You have the controls", I grasped my controls and I replied "I have the controls", then he replied "You have the controls" and sat back and crossed his arms and watched.
To my amazement I was hovering. This lasted maybe 15 seconds before I started to drift. The next 45 minutes, we pretty much covered all the 150 acres of that field, I can recall at one time getting at least 100 feet in the air, and I suspect at one point was moving in excess of 40 knots in various directions including backwards. All this time, Mr. Rhoads made no offer to assist me and somehow I never did anything so absolutely dangerous that he would take the controls. I requested he take the controls back and he quietly replied that when the aircraft was back where he'd given me the controls and in the same attitude, he would, until then I was on my own.
Eventually, with the minimum of suggestion from my instructor, I figured out that I was "Over-controlling" the aircraft. All control inputs had to be done with a delicate touch, and you had to wait momentarily, because there is an ever so slight delay in just about every control input. In this little bird, it is almost imperceptible, as it is mostly the throttle response of the 180 HP engine that accounts for the lag. I also think that sheer exhaustion was a contributing factor. Regardless, I finally was managing to herd this craft in the general desired direction and eventually achieved a 3-foot hover, in a generally southern facing direction, when a tire out in front of the aircraft. Mr. Rhoads took the controls and I just about collapsed in my seat.
Other days in the first couple weeks of flight school were completed at Hooper stage field. Hooper always had a place in my heart as it was the closest stage field to Ozark, Alabama. Where I was renting a house. As a matter of fact, the house was in the downwind leg of the traffic pattern for lanes 1, 2 & 3 of the stage field. Hooper like most the stage fields, had 6 lanes. Each lane was a paved tarmac (Aviation term for blacktop) and was 1600 feet long. At 400 ft. increments there were pads 1 through 4 and a takeoff pad at the far end.
Near the road were parking pads the tower and bleachers were the second session students waited for their turn. (Two students per instructor, we each flew for about an hour a day then swapped out). After an average of 7 to 9 hours you get to fly your first supervised solo flight. I'll tell that tale the next blog entry.
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