Flying the Kaman H-2A/B SeaSprites
My first memories of the UH-2A are from a Sunday afternoon walk around on a deserted Whiting Field transient ramp when I was still in the Basic phase of the training command. The helo had flown in from the Naval Air Station in Mayport, Florida and sat there, sleek looking with its blades folded back.
At the time, I was hoping to finish basic flight training and get my first carrier landings in the T-28 and then go on to Corpus Christi to fly A-1 Skyraiders or SPADS as they are known or to transition to jets and fly F-8 Crusaders or F-4 Phantoms. Peering through the Plexiglas window on the door, there were a lot of strange, at least to someone who had flown only fixed wing aircraft, instruments in the cockpit.
Fast forward about eight months and along with dashed dreams about flying A-1s or fighters, I reported to my first squadron, Helicopter Combat Support Squadron TWO or in Navy parlance HC-2. How the assignment to helicopters happened is another story. As a pilot, my introduction to the H-2 came when the the squadron operations officer told me that I was going out on a detachment flying the UH-2B. This, like a lot of things, changed from one day to the other and the result was that after about fifty hours in the both As and Bs, I moved on the UH-2C.
Four things stick in my memory about the H-2A and B. One, you learned all about droop. Droop is the reduction in helicopter rotor rpm as you increase power to maintain a hover. What happens is the engine doesn’t produce enough torque and rotor rpm begins to decay causing a loss of lift. As a result, droop “officially” occurs when the rotor RPM drops below one hundred percent rotor. If the rotor RPM droops below a certain speed, bad things start to happen such as you lose lift and can’t maintain a hover or fly or the generators and hydraulic pumps go off the line. Get too low on rotor RPM and you fall out of the sky like a stone.
Two, never fill a UH-2A or a B full of fuel because you may not have enough power to hover to make a rescue or land on the back end of a destroyer. So any flight evolution that may require a hover of some sort will require you to dump fuel to get down to a weight at which one can maintain a hover. To get off the ground or the deck of a carrier, you had to plan on a short rolling take-off to get the helicopter into translational lift. On the flight deck of a carrier, you could do it easily. On the back end of a destroyer, you couldn’t because there wasn’t enough space. Roll in forward and the tips of the rotor blades would slam into the superstructure of the ship. From there, really bad things would happen, the worst of which would be you would be trapped in a burning helicopter that was trying to beat itself to death.
Squadron standard operating procedures said never fill up an H-2 A or B with full fuel in you didn’t have room for a rolling take-off or you were going to need to hover in the first hour of the flight. We started with 600 hundred pounds – about 90 gallons – of fuel which was about half its capacity.
Somewhere around 15 – 20 knots, translational lift occurs because the horizontal airflow across the individual rotors acts as a solid disc and the result of phenomenon is that the helicopter has about 10 -15 percent more lift for the same power setting.
In an H-2A or B, if you started with more than 600 pounds of fuel on a carrier, you had to do a running take-off to get into translational lift and the distance was based on how much wind over the deck the ship was providing. The more wind over the deck, the shorter the take-off roll.
Three, know where you could get fuel. Until you were about halfway through almost any flight in the UH-2A/B, you needed to dump fuel in order to hover. We often cheated and loaded up with about 800 pounds of fuel (118 gallons) knowing that if we had to hover, we would have to dump fuel. So, if one took off from a carrier on a typical plane guard mission on a hot day in an H-2A or B, before you could pick up the survivor, you’d have to spend time dumping fuel in order to get down to a weight at which you would be able to maintain a hover. While this may not sound important if one is a few miles from the carrier, the story is very different if the survivor is fifty or a hundred miles away. After the pick-up, there was a good chance that the helicopter did not have enough to get back to the carrier. A smart HAC always knew where the nearest aviation capable ship was because it could keep you from getting wet!
Fourth, we didn’t practice full auto rotations in the H-2s (or the H-3s). When I first arrived, we were allowed to do full autos in the A/B models, but not the Cs and later, the Ds. In a full autorotation, the helicopter descended power off and flared to kill any forward airspeed and as the pilot traded rotor RPM for height as you let the helicopter descend to a gentle touch down.
In the training command, we did full autos in the TH-57 and the UH-1D which came down at a manageable rate of descent and when you were about fifty feet above the ground you flared to slow to zero ground speed. As you flared, the RPM would increase and you could then let level the helicopter and let it gently settle on its skids.
There is a big difference in the distance a helicopter can autorotate and a fixed wing airplane can glide. Airplanes can, depending on the altitude can glide for miles. In helicopters, the distance covered over the ground in an autorotation is measured in fractions of a mile.
In the heavier H-2s (and H-3s), you came down like a streamlined rock. When you felt the collective hit the bottom stop at the practice autorotation’s starting altitude of 1,000 feet above the ground, your landing spot would be next to your feet! You found it by looking through the Plexiglas window below the rudder pedals or just over the nose. In other words, you weren’t gliding very far and if you tried to turn, the distance to the landing area decreased even more.
So instead of flaring and touching down, the “practice auto” in the H-2 and H-3 involved descending, flaring and the exercise ended as you descended through 10 to 15 feet in the H-2 (40 in the H-3) with 10 to 15 knots (five to 10 in the H-3) forward airspeed before waving off. You didn’t touch the ground and full autos were prohibited because they were considered too dangerous.
Even though most of the flying we did was over water, practice autos over the water were prohibited. Why? The answer I got was because it was hard to judge one’s height over the water! So, let me get this straight. We’re going operate off destroyers, cruisers and carriers at sea most of the time and if we have to make an emergency autorotation to ditch the helicopter, we can’t practice them because it is hard to judge one’s height over the water. It didn’t make sense then and, five decades plus later, it still doesn’t!
Hi, Marc.
As a “tweet” I occasionally rode along on some flights to troubleshoot – usually a doppler issue or something that I just could not duplicate on the ground. On one such flight we finished with a few practice autorotations (SH-3A or G – can’t remember) at Ream Field. I thought it was great fun at the time. Sort of like a roller-coaster ride. Since I was plugged into the ICS in the aft station, I was asked several times if I was having any problem keeping my lunch down. No problems in that regard. I was turn-qualed and “flew” the WST a few times, but this was my only (thankfully) experience with doing “Autos”.
Ed,
Right about the time I left the ASW/H-3 world, we were told to stop practicing autorotationn! The H-3 came down like a stone (as do all helos) and if you are not prepared for the sudden lowering of the collective, it can play havoc with your stomach. I had several air crewman almost lose their lunches….
marc