Helicopter Anti-Submarine Squadron 5 pioneered all-weather night operations in the early 1960s, searching for Soviet subs in the North Atlantic.
On June 30, 1960, I attended a small ceremony where I received my U.S. Navy wings of gold after 18 months of training. It was a joyful experience following months of stress and anxiety as I stumbled through the many training phases and watched friends fall to the demands of the intensive curriculum. I was a lucky one who survived. Very lucky.
In 1959 the Navy had not yet developed a discrete program to train helicopter pilots. “Real” pilots flew airplanes. During training we flew North American T-28s and Beechcraft T-34s through a full curriculum of aerobatics, formation, instrument flying, cross-country navigation and gunnery before moving on to multiengine instruction in the Beechcraft SNB (C-45) and finally to three months of helicopter training.
I was subsequently assigned to Helicopter Anti-Submarine Squadron 5 (HS-5) at Quonset Point, R.I., flying the Sikorsky HSS-1 Seabat. The 14,000-pound HSS-1 (redesignated the SH-34G in 1962) was a large helicopter for the time, powered by a 1,525-hp Wright R-1820 radial engine. The Wright Cyclone had been successful in several World War II airplane applications but it was not very reliable in the HSS series, as it ran at or near full power for most of a four-hour mission. A 300-hour engine was considered high time.
By 1960 there were several squadrons on both coasts operating the HSS-1, though only in daylight and fair-weather conditions. Tactics had been developed for visual operations but there was no night/all-weather capability because the automation necessary for a complete transition to hovering flight had not been developed. While we could fly at night and in instrument conditions, at the time it was impossible to hover a helicopter without visual contact.
Hovering was essential to the mission because the AN/AQS-5 sonar suite worked through a transducer ball that was lowered into the water by a cable. That cable was limited to a speed of 5 knots through the water to prevent stretching it and damaging the fine electronic leads inside.
At that time the Soviet submarine threat was a high priority for the Navy, which operated two task forces (Alpha and Bravo) that patrolled the Atlantic, frequently in or near the GIUK Gap, the channels between Greenland, Iceland and the United Kingdom through which all Soviet subs had to transit coming and going. Each task force centered on one Essex-class carrier with Grumman S2F airplanes and HSS-1 helicopters working in coordination. My ship was USS Lake Champlain, the Navy’s last straight-deck carrier. The force also comprised six destroyers and one SSK hunter-killer submarine.
A typical mission saw a formation of four helicopters dispatched to a datum area to run sonar search patterns for a possible submarine until surface units with more powerful sonar arrived. Often the helicopters would screen for subs ahead of the carrier. We would also occasionally perform utility tasks, transporting personnel and materiel between ships and flying guard for landing airplanes.
One unique aspect of this time in the helicopter community was that there were almost no senior officers with previous helicopter experience. All of HS-5’s senior officers had been recycled from patrol and other fixed-wing backgrounds or blimps, so squadron pilots of all ranks had roughly equivalent experience. It was akin to being in a U.S. fighter squadron in 1917. Further, because the more senior officers were tasked with the typical workloads of department heads, the majority of flying was done by junior officers.
Then in 1961 my squadron received seven HSS-1Ns (later SH-34Js) from Sikorsky equipped with a system designed to fly the helicopter in all weather and night conditions, including automatic transition from level flight to a hover at 35 feet, a remarkable step in automation. These Seabats were delivered with the suggestion that they be used only in visual conditions until Sikorsky developed the appropriate procedures for night flying. Several other squadrons had received the same helicopters with the same instructions. The difference at HS-5 was that we had a CO who was a test pilot graduate and an aggressive leader. Commander Robert W. Raddatz authorized squadron pilots to fly the HSS-1N as designed and assured us that he would have our backs as long as we did nothing stupid or illegal.
The procedure for which the HSS-1N was designed was quickly dubbed “night dipping” and we logged those approaches to a hover in the dark the way fixed-wing guys logged carrier landings. In fact, HS-5’s successor, HSC-5, carries the official nickname “Night Dippers” to this day.
Before a typical night mission, Bernie Woessner and I would brief in the ready room with three other crews. Woessner was an ex–merchant marine officer, an excellent pilot and good friend of very few words. A conversation with him was often not much more than a long pause followed by “Yup.” Nearly 60 years later we are still friends.
Ken Cluckey, our sonar operator, was excellent at his job but prone to mischief. His hobby was waiting until last call on Saturday night, ordering one more beer and then biting the bartender. Not hard, but a bite that would land him in the brig overnight. Monday morning would start with a subdued Cluckey confessing, “Mr. Manningham, I’m so sorry. I bit another bartender.” But then with a grin he would add, “That’s number 28!” Cluckey was secretly proud of his total. And I didn’t care. He could bite all he wanted as long as he continued to have the best sonar ears in the Atlantic fleet. In the helicopter he was an exceptional crewman. Crew 16 was unconventional but we were often effective.
Night takeoffs could be tense if our helicopter was spotted beside the carrier island or near parked airplanes, which was the norm. Rotor clearance was minimal, visibility was severely limited and it was imperative to break the deck in a drift away from any obstacle to avoid contact. In warm weather, performance was limited since we were always at max gross weight at liftoff.
Transition to the search area was directed by radar vectors, as we had no means of navigation other than dead reckoning. Navigation was by grease pencil on a plastic plotting board, supplemented by occasional radar vectors from surface vessels. At the datum area the flight would break up and begin an expanding search on four independent compass legs, and dipping would begin.
Night in the North Atlantic was dark, utterly dark. We were isolated because there was limited or sometimes no communication with the ship. And it was bitterly cold for two reasons: the ambient temperature and the fact we flew at all times with the sliding cockpit windows open because an engine failure at low altitude would not allow us enough time to open them for escape. We did wear survival suits (“poopy” suits) that would extend our survival in arctic water by an hour or less, but they were bulky and cumbersome.
To initiate the dipping procedure, I (or Woessner if he was flying) would establish the helicopter at 130 feet above the water and about 70 knots indicated airspeed, flying on the automatic stabilization equipment (ASE), an early helicopter autopilot. We moved the mixture control to rich because it was required for the high engine power settings in a hover, and checked the R-1820’s instruments.
To begin the automatic transition to a hover, the non-flying pilot engaged two green-lit buttons on the central console for lateral and vertical control and the rest was automatic. The helicopter began a descent guided by doppler wave-sensing and radar altimetry. The doppler system was not especially accurate and the altimetry was working off waves, so the helicopter wobbled and oscillated over the surface and the throttle fluctuated in response to those moving waves. It was an unstable, shaky, rock-and-roll ride to 35 feet. As the helicopter slowed through the speed for translational lift—about 30 knots—the natural aerodynamic buffeting shook the instrument panel into an unreadable blur for several very uncomfortable seconds at the most vulnerable time of the approach.
At 35 feet I called to Cluckey, “Lower the ball,” and he initiated its descent. When the ball had descended 20 or 30 feet Woessner switched the lateral control from “Doppler” to “Cable,” resulting in an immediate, very stable hover. After the ball entered the water the altitude mode could be switched from “RadAlt” to “Cable,” with a similarly stabilizing effect on altitude.
When it all worked it was marvelous, but keep in mind this was 1960s vacuum tube equipment. There were multiple failure modes, each of which could produce unnerving results, not to mention this was all a recipe for vertigo. On one mission Woessner was flying and at the critical point as we entered a hover he said, “Take it, I have vertigo.” I grabbed the controls but when I looked at the panel I had vertigo too, so we froze the cyclic (the main rotor control) where it was, pulled the collective (controlling rotor pitch) to our armpits, popped up a couple hundred feet and somehow got moving forward and back to stabilized flight. Then we tried it all over again.
When we did get established in a hover, Cluckey could begin a sonar sweep with equipment that was primitive by modern standards. The AN/AQS-5 was a so-called “searchlight” sonar that could only look at a 10-degree arc. Cluckey had to make 36 individual searches using nothing but his ears, since there was no visual display. He listened for ambient noises in the water or the return from an active “ping.” A complete sweep required at least five minutes. Extreme range was about 3,000 yards.
When Cluckey completed his sweep, assuming there was no contact, he retracted the sonar ball and we manually flew the helicopter away from the hover and back up to a safer altitude. Then we moved to the next search location and did it again…and again. This was typical of anti-submarine warfare (ASW), like looking for a wedding ring you lost somewhere in the lawn while mowing. But Cluckey was very good. Sometimes we found the gold ring and then we launched a full-on track using all available air and surface assets with the ultimate goal of forcing the sub to surface.
The final flight element that needed to be redefined for night/instrument flying involved autorotation in the event of an engine failure. In the dark over the ocean there is no visual reference for final flare and touchdown during that tricky maneuver. So Sikorsky developed a modified procedure that involved four steps: bottom the collective, turn the helicopter into the known wind, slow to 30 knots and, at 50 feet on the radar altimeter, pull the collective lever to use rotor inertia and hope for the best—all of this to be accomplished in a minute or less. HS-5 lost two helicopters practicing this maneuver, one on land and one at sea.
Since those early days developing all-weather, day/night helicopter anti-submarine operations, HS-5 has morphed into Helicopter Sea Combat Squadron 5 (HSC-5), part of Carrier Air Wing 7 based in Norfolk, Va. HSC-5 has a much more comprehensive mission that nevertheless includes day and night dipping with sonar.
Why does all this matter? Because a handful of young pilots and technicians, under a capable and confident commanding officer, put their lives on the line to establish working procedures for a mission that has since become a worldwide standard. Because international conflict happens. Because submarines are an ever-increasing threat and helicopter ASW has a distinct heritage that began 60 years ago.
Dan Manningham spent 45 years actively flying, including five years in the Navy and 33 years with United Airlines. He is the author of three books and some 500 articles for professional pilots. Further reading: Sikorsky H-34: An Illustrated History, by Lennart Lundh.
This feature originally appeared in the March 2020 issue of Aviation History. To subscribe, click here!