Flying the Sikorsky H-3 SeaKing

The H-3 is the Chevy Suburban of helicopters. It is adaptable, functional, and for its day, pretty reliable. The H-3 is or was flown by the armed forces of 15 countries – Argentina, Brazil, Canada, Denmark, India, Iran, Iraq, Italy, Japan, Malaysia, Peru, Spain, the United Kingdom, the United States, and Venezuela – and were built in the Canada, Italy, Japan, the U.K. as well as the U.S. More than 1,300 H-3s of all types were built and there are so many military and civilian variants that it would take a book to describe them all. This discussion focuses on the Navy variants I flew rather than the Air Force CH-3C/Es and the Coast Guard’s HH-3Fs.

The official name for the Navy versions of the H-3 is the Sea King. The helicopter was designed in the mid to late 1950s as an anti-submarine helicopter that took advantage of the additional power and capabilities of turbine engines. As a result, the H-3 had a large cabin on top of a boat shaped hull and sponsons for stability should one have to ditch. The large cabin was needed to house the reeling gear for a sonar dome that could be lowered into the water to listen or ping for submarines.

The original AQS-8 sonar installed in the H-3 had about 150 feet of cable which, when lowered through a hole in the H-3’s cabin floor from a 40 foot hover to about 100 feet below the surface of the ocean. Later U.S. versions had the AQS-13 sonar, which besides being more reliable, smaller and lighter, had 1,200 feet cable on the reel. The sonar reel and two sensor operator stations took up most of the cabin in the ASW version of the H-3.

The mission for the ASW H-3s was to go 50 to a 100 miles or more from the carrier and lower the sonar dome into the water and listen for submarines. We called this “dipping” and did this day and night, regardless of the weather. By operating in pairs, one H-3 could hold contact on a submarine either by active pinging or listening passively for noise emanating from the submarine and direct a wingmen to a position ahead of a maneuvering sub. Or you could vector a fixed wing aircraft to the targeted submarine.

If there was a problem with the sonar dome’s hoist, the crew had two options, one was to cut the cable and let the expensive sonar transducer sink to the bottom of the ocean. Or, you could climb straight up until you got the transducer a.k.a. “the dome” out of the water, fly back to the ship, wait for everyone else to land. As you circled the ship, the deck crew laid out a pile of mattresses. You were directed to a hover and lowered the dome onto the padded surface. With the dome safely on the mattresses, the pilots descended vertically as the men on the flight deck crew tried to coil the cable. Ideally, one could unwind the cable in a hover and when it was all out, the aircrew could disconnect the cable from the reeling machine. Or, you were ordered to guillotine the cable and come around and land.

The worst scenario was while dipping with a lot of cable out and you had an engine problem.  If that happened, there was a very high probability that you were going to ditch. Whomever was flying the helicopter in the hover had his thumb over the guillotine switch because if you were fast enough, you could cut the cable and fly away. In the daytime, this was difficult and depending how much fuel had been used, the H-3 would start to settle and you’d have to decide how much rotor rpm you wanted to trade for altitude.

At night, darkness and the lack of a well defined horizon made it much worse.  Unless you were really quick and skilled, an engine failure at night with the cable out meant you were about to make a single engine water landing.  The key was touching down, wings level at less than five knots at a slow rate of descent. If you managed to get the helo in the water without major damage or it rolling over, you had a chance to spend the rest of the night in the water or dumping as much gear as you could and trying a single engine, night take off before the H-3 took on much water.  Was it possible, yes.  Has it been done, yes.  Have I done it?  Thankfully no!

The H-3 also had four ordnance stations, two on each side of the hull. Theoretically, we could carry the Mk 58 primarily to carry the Mark 44/46 lightweight torpedo, depth charges, including the B57 nuclear one! There was even a training film on how to arm and drop the B57.

One time, we carried a multiple ejector rack on the forward stations and loaded each with eight Mk. 76 practice bombs. The mission for the day was practice dropping ordnance and since we couldn’t do it over the water, we rolled in on targets on a bombing range south of Jacksonville. Imagine dive bombing in a helicopter. It was fun, but the racks disappeared along with the training hop requirement.

We even hung chaff dispensers on the ordnance stations as well as, on the forward ones, external fuel tanks. D models had extended sponsons that carried smoke flares and magnetic anomaly detection equipment.

The MAD bird, as it was called, was towed about 150 behind and about 50feet below the helicopter and detected changes in the earth’s magnetic field made by large metal objects, i.e. submarines. When it was out, you had to be careful of your altitude because the closer the MAD “bird” was to the water, the deeper its detection range. All the Navy fixed wing ASW aircraft had MAD booms that extended out behind the tail.

The H-2s were much more maneuverable than the H-3 but they didn’t have the range, cabin size or payload of the H-3. So, for rescue missions during the Vietnam War, the Navy began to task H-3s assigned to ASW and utility squadrons for combat search and rescue. The H-3’s range and payload made it ideal for the mission but very quickly, the Navy realized a dedicated combat search and rescue helicopter was needed.

Enter the HH-3A. In a crash program, the Navy modified twelve SH-3As into HH-3As by taking out all the ASW gear and fitting self-sealing tanks, armored seats and mounts for a GAU-2B/A 7.62mm mini-gun firing out the cargo door on the right side and a 7.62mm M-60 shooting out the passenger door on the left side, just behind the co-pilot’s seat.  Composite armor plates were added around sensitive hydraulic and flight control components along with some on the floor and by each of the doors.

They were painted a dull gray or matte black and a small, U.S. “star and bar” insignia was in a noticeably darker shade of black. The GE T-58-8F turbo shaft engine gave the HH-3A 1,450 horsepower which was about 200 more than the original ASW models to improve performance.  However, the modifications jumped the empty weight jumped from around 12,000 pounds to close to 14,000. Instead of taking off at a maximum designed gross weight of 19,400, the HH-3A, with a crew of four or five – pilot, co-pilot, rescue swimmer and one or two gunners – often weighed at much more depending on how much ammo and other gear the crew was carrying. These helicopters became the workhorses of Helicopter Combat Support Squadron SEVEN (HC-7) whose squadron’s official name is the Sea Devils but is better known by its unofficial name and call sign Big Mother.

Even though the H-3 had a theoretical top speed of 140 knots, as the age and weight of the H-3s increased, the top speed dropped. When I was flying them, getting 110 – 120 out one was all you could manage. By the time Desert Storm rolled around, the top speed of the SH-3Hs was reduced to 90 knots because the Navy wanted to reduce the stress on the rotor blades and increase their life.

One entered the H-3 through either the passenger door on the left side just aft of the cockpit. The top half went up while the lower half provided steps. Or, one could clamber up and go in through the large, sliding cargo door at the aft end of the cabin. Once inside, one could stand upright, unless you were an NBA basketball player. It took a step up into a spacious cockpit which had what looked like two thrones, one on each side of the center console.

Anyone who has flown the H-3 will tell you that the seats were not thrones. Instead, they were pilot torture devices designed by the Marquis de Sade! Sikorsky created the most uncomfortable seats known to aviation. We were told their design minimized the damage to the pilot’s spine in case of a hard vertical landing, i.e. a crash by telescoping to absorb the impact. I never had to test the theory, but good God, they were uncomfortable. Double cycle missions when we were in the cockpit for eight to nine hours were painful experiences.

Once ensconced in the flight deck, the view was spectacular. Unlike the H-2, where everything was close, the windscreen in the H-3 was well out in front of you and the side windows were eight to 10 inches away from the seat which gave the cockpit a feeling of spaciousness. Like the H-2, the H-3 had Plexiglas windows under the rudder pedals which I never understood why they were there other than to see where you were about to land if one had to autorotate.

Along the roof of the cabin, fuel and hydraulic lines along with several wiring harnesses were clamped side by side to the fuselage’s ribs and longerons. This simplified troubleshooting and made repair easy. Their location also made them extremely vulnerable to enemy fire. In the non-ASW versions, there were canvas bench seats along the cabin walls. Depending on the model, there were seats for anywhere between six and nine passengers.  On one flight when we were rescuing survivors from a hurricane in Pennsylvania, we had 30 people and pets crammed into the cabin.

Flying the H-3 was easy but you were always mindful of its size. Although the rotor blades were only 25  feet long, the diameter of the rotor system from tip to tip was close to 60 feet which was about 20 wider than the H-2s. The Navy used the H-3 like a mid-sized pick-up truck. If you could get something inside, the assumption was that one could fly away unless it was made of lead.

The G models had an external hook for carrying large loads that wouldn’t fit in the cabin. The SH-3G was modified so that the ASW equipment could be easily removed, a floor plate installed over the hole through which the cable was lowered so the G could perform as a logistics helicopter. I rarely flew a G model that had an operable sonar system installed.

When flying the G models we were often asked to carry bulky parts from the carrier to a smaller ship in the task force. Normally, that mission was flown by the vertical replenishment squadrons flying the twin rotor, H-46.  Since the aircraft carriers didn’t have any H-46s assigned to the air wing, the ship assigned the mission to the helicopters on board.

Flying parts, people, and mail from the carrier to another ship was simpler and faster than having the destroyer come alongside the carrier and sling the large cans or pallets between ships using lines. When the parts came out, for us to carry, they all had tags showing their weight. Every H-3 crew looked at the tags, out of necessity, before the item was loaded for two reasons – would it fit and can the helicopter lift  the weight.

On one occasion, as we approached for landing after being airborne for about three hours, the Air Boss asked if we could take some cargo to one of the escorts about 100 miles away. We shut down the rotors so we could load the cargo and take on fuel. I never take off without a full bag of gas because experience told me that I never knew where my helicopter would be sent next and ships were often not where they said they were.

This is not to say ship captains are malicious, but back in the old days when there were no ship to ship data links or GPS, they relied on celestial navigation.  You were given a bearing and distance to the ship based the last reported position which could be several hours old. Ships at sea move about in their assigned block of sea space and the difference between one end and the other could be 20 or 30 miles. In this instance, the co-pilot and I alternated running to the head (bathroom) while the pallet was loaded via the cargo door.

When I saw the mini-forklift by the H-3, I should have known something was wrong. As strapping back in, I asked the senior air crewman who was new to our detachment, how much the pallet weighed and he reported back that the weight tag said 260 pounds which also matched what was on the manifest. I figured the forklift was needed due the bulk as opposed to the weight.

As we started to lift off with full fuel, the rotor RPM drooped as I pulled power and we weren’t getting light on the wheels. Sensing there was something wrong, I had one of the air crewman get out and walk around to see if any chains were still attached to the helicopter. Finding none, we tried again with the same result. By now, the carrier’s air boss was impatient because he wanted to land airplanes on the angle and we were in the way. So, again, I pulled power and the rotor rpm dropped to 96 percent and still, the H-3, now with full fuel on board, wouldn’t come off the deck.

Being the resourceful HAC and not wanting to tell the air boss we couldn’t take off without having a good reason, I eased the cyclic stick forward to make a running take-off. The H-3 settled rapidly as we rolled off the front end of the angle of the carrier which was making about 15 knots at about 40 knots of airspeed. We managed to level off without hitting the water and by milking the collective (a technique I learned and practiced in the UH-2A/B), we staggered up to about 200 feet a couple of miles from the carrier. Milking was a technique where one added power and let the RPM droop to a specific rotor speed and then eased down to regain rotor RPM. In Big Mother 40 the technique is described in detail.

Once I had the H-3’s rotor RPM back up to 102 percent, the normal operating rpm.the air crewman began, at my encouragement, to look around the packaging to see if there was any indication of its true weight. Lo and behold, he found markings that said the container weighed 2,600 pounds, not 260 on the weight tag given to us by the carrier’s air transport officer!

All the H-3’s flight controls were hydraulically boosted which meant that you didn’t need a lot of strength to move the cyclic stick, collective or the rudder pedals. The helo had two separate hydraulic systems for flight controls and one for the brakes, raising and lowering the landing gear and the blade fold system.

As effective as they were, they were also the helicopter’s Achilles heel. In Vietnam, the H-3 was being asked to fly missions that its designers never intended it to fly, i.e. combat search and rescue. All of the hydraulic actuators for the main rotor system were located in a compartment behind the pilot’s seat called the broom closet.

The HH-3A had armor around the broom closet that would stop 7.62mm rounds, but anything larger could penetrate the armor. A 12.7mm or worse, a 23mm round exploding in the broom closet would bring down the helicopter because both the 1,200 psi (pounds per square inch) hydraulic systems and/or the actuators would fail making the H-3 uncontrollable and seconds later everyone one on board was was dead.

Another vulnerable area was the area just aft of the transmission where the two hydraulic reservoirs were located. Between the transmission which would run for less than 30 seconds without oil before seizing and the need to have at least one of the hydraulic systems functioning in order to control the H-3 made the helicopter very, very vulnerable to ground fire.

The first H-3’s carried 4,500 pounds or about 750 gallons of jet fuel. In a 90 t0 100 knot cruise, the fuel burn was about 1,000  (that’s about 150) of jet fuel (the Navy calls it JP-5) per hour. In a hover, the fuel consumption was much higher. Most missions were planned for four hours because the low fuel warning lights came on with about 20 minutes of fuel left. Later versions had two, 110 gallon drop tanks which extended the time in the air to about six to six and a half hours depending how much time one spent in a hover. The D models had what we called the doughnut tank which was an extra fuel cell around the hole in the floor. This gave the D model six plus hours of internal fuel.

One of the great things about the H-3 was its auto-stabilization equipment, a.k.a. the “ASE” and auto hover capabilities. Early on, when flying the H-2, I learned how to hand fly an approach to a 40 foot hover at night. The first few times, getting to a hover, much less hovering at night, is a hair raising, sweaty palms experience. The pucker factor is always high because of the proximity to the water and all the variables that can easily result in an uncontrolled water landing.

By the end of my first cruise, I actually enjoyed hovering at night satisfaction of doing something well that was very difficult. Unlike the H-2 whose auto hover capability was, at best not very reliable, the H-3’s was a dream. Yes, you had to monitor it all the time – who wouldn’t – but the approach to and the auto hover feature worked well in the A models and even better in the later D, G and H models.

The H-3 could be trimmed and maneuvered using the autopilot while in a hover. This capability was critical when the sonar ball is several hundred feet in the water but is also very important during a rescue while you are trying to maintain a stable, steady hover while trying to pluck someone out of the water.

For rescues, the standard procedure was to come into a hover close by the survivor and then the senior air crewman would guide you over the survivor.  Once there, we could transfer lateral movement of the helo to the air crewman who had a a joy stick through which he had very limited control of the helicopter. The joy stick would be overridden by any control inputs by either the pilot or co-pilot who maintained a steady hover at 40 feet.

The H-3 was also great instrument platform and had decent range which made the helicopter, a pretty good cross country machine. The H-3 was stable and easy to control and trim as long as the ASE was working. Without the ASE, flying an H-3 on instruments was like trying to stand on a rapidly rotating greased sphere.

There were two other things one had to be mindful about the H-3. First, unlike the H-2, one had to be very careful when doing quick stops. If one flared (raised the nose) too violently, the main rotor blades would flex and could hit the tail pylon. At the very least, one would damage one of the main rotor blades and create a hellacious vibration that could cause the rotor blade to come off. Or, it could damage the drive shaft to the tail rotor causing a loss of tail rotor control or worse, do enough damage to the tail pylon so that it could come off. All of these could ruin your whole day!!!!

Second, landing on destroyers and cruisers in the H-3 was a challenge. In the H-2, with a smaller rotor diameter, was easier to land on what we referred to as “small boys.” Back in the early seventies, helo decks were often added as afterthoughts to the ship years after it was built rather than, as is the custom today, to include a helicopter deck in the original design.

I’ve landed on destroyers, frigates, light cruisers, heavy cruisers and even battleships in good weather and bad. The worst was trying to land on a destroyer that was rolling +/- 15 degrees and the deck going up and down about 20 feet. In most cases, the larger the ship, the larger the helo deck, but that was not always the case. During the Vietnam era, there were large destroyers called DLGs that had decks designed for much smaller helicopters. DLG stood for “destroyer, leader, guided missile.” Later, the ships were renamed CGs or “cruiser, guided missile.” On many of these ships, the clearance between the H-3s rotor tip to the ship’s structure was often less than 10 feet and on some, less than six.

While this seems like a lot of room, keep in mind that the ship was often pitching and/or rolling. During the day and in a smooth sea state, landing on a destroyer required careful flying but was more or less “routine.” At night, the pucker factor went way up and if the weather was bad, i.e. rain or worse, snow and the deck moving up and down five to ten feet makes it much more challenging.

Getting the H-3 down on the right spot wasn’t a matter of precise flying, it was a matter of life and death because a little left or right and one main mount was off the deck and you could to roll off into the sea. Too far aft, the tail wheel was off the deck and the helicopter could roll right or left as the tail rotor came off. Too far forward and the rotor blades were beating themselves to death against the ships superstructure.