U.S. Navy Aircraft History

By Tommy H. Thomason

Wednesday, September 30, 2015

Carriers and Tricycles

Except for a few very early biplanes, for many years airplanes had tail wheels, not nose wheels, even though the latter made landings less likely to result in excursions off the runway or worse. The reasons were compelling. A nose gear was more likely to break during a landing (or even a takeoff) in the former pastures that were used for landing fields, it was heavier than a tail wheel, and before the adoption of retractable landing gear, resulted in more drag in cruise flight.

However, paved runways eventually became the rule rather than the exception. Retractable landing gear made the nose-landing-gear drag penalty disappear. The nose landing gear arrangement also became of benefit during the takeoff roll of a multi-engine airplane: in the event of an engine failure, the pilot was more likely to be able to keep the airplane headed down the runway if it had a nose wheel to help resist the turning moment. In fact, it was more widely incorporated on early bombers like the B-24, B-25, B-26 etc. than fighters. (One exception was the P-38 but the configuration of the former wasn't really suitable for a tail wheel and it was also multi-engined.)

Another exception was the Bell P-39. It's unique inline arrangement of cannon, cockpit, and engine provided room for a nose gear and the need for nondisposable weight up front for balance reasons.

The Navy's preference for a tail-wheel configuration was so strong, that when it agreed to consider a carrier-based variant of the Army's new fighter, it insisted on it. The resulting Bell FL-1 became a taildragger.

For more on the brief history of the XFL-1 Aerobonita (as well as a summary of the history of the development of—and the engine manufacturer's struggle for supremacy between—the air-cooled versus liquid-cooled airplane engine and the Navy's ongoing interest in the liquid-cooled engine) see my monograph;
It is available from Steve Ginter here: http://www.ginterbooks.com/NAVAL/NF81.htm

The Navy didn't completely forswear the nose-wheel configuration any more than they did the liquid-cooled engine. In August 1939, they went to the trouble of converting a Lockheed Junior to have a nose gear (it was fixed and the main landing gear had to be moved aft as well) and conducting successful at-sea trials aboard Lexington (CV-2).

Douglas won contracts during World War II for two single-engine carrier-based attack planes with nose landing gears, the SB2D and TB2D:

My guess is that the advantage was that heavy bombs and torpedoes didn't have to be positioned at an angle to be attached to the airplanes. A small quantity of BTDs,  a development of the SB2D, were built for evaluation. Douglas quickly replaced it with an all-new design with a tail wheel, the BT2D, which became the AD Skyraider.

The Ryan FR-1 also needed a nose wheel because it had a jet engine in the tail. From time to time, it was a poster child for the benefit of not having a nose landing gear during a carrier landing (as well as proper location of the attach point for the tailhook).

Nevertheless, the nose wheel configuration also went to sea on the Grumman F7F Tigercat, albeit rarely and not without incident:
The F7F's main contribution to carrier-based aviation was the need for the development of a crash barrier that was compatible with airplanes with nose landing gears. See http://thanlont.blogspot.com/2010/10/barriers-and-barricades-one-more-time.html

Jets, of course, all but had to have a nose landing gear for various reasons. There were a few exceptions early on, even one that was carrier based, the Supermarine Attacker.

For more on twin-engine carrier-based airplanes with nose landing gears, see http://thanlont.blogspot.com/2010/11/one-if-by-land-two-if-by-sea.html

Monday, September 14, 2015

TailDragger Transition

Mark Frankel and I are in the process of finishing up our book on U.S. Air Force and U.S. Navy trainers, Training the Right Stuff. It will be published by Schiffer in the spring.

One major feature of the new post-World War II trainers was that they had nose wheels (tricycle landing gear) rather than tail wheels (taildraggers). Landing an airplane with a tricycle landing gear was a lot less likely to be dramatic because it was directionally stable. A taildragger was not, some more inclined to swap ends than others, but none that didn't bear watching, particularly in a crosswind. There were other advantages to the tricycle landing gear, such as being able to see where you were going when taxiing or beginning a takeoff.

One shortcoming of an all-tricycle training fleet was that there were still taildraggers in use. However, most had dual control or dual-control variants, including the P-51 Mustang. And transitioning to a taildragger was somewhat easier if you already knew how to land. In the military, if an aviator had gotten that far, he would be less likely to be off optimal (airspeed, rate of descent, and alignment with respect to crosswind and runway) on short final and quicker to correct a problem like a swerve or a bounce.

What hadn't occurred to me, but did to Frank Williamson, was how did a Navy pilot go from the tricycle-gear T-28 into the AD Skyraider? The Navy didn't have any with dual controls (the Air Force did later on, since the AD-5 had dual-control provisions). The answer was advanced training at Navy squadron VT-30 at Corpus Christi.
Richard Adams via Phillip Friddell

Walt Fink was one of the aviators to do so:

Been there and done that in July 1962. Skyraider "Fam" at VT-30 consisted of five AD-6 (single-seat, because that's all we had—no Fat Spads) "flights"—that in quotation marks because on the first one, we didn't ever get airborne. It was a ground exercise to acquaint us with the taildragger mentality but we prepared for it like we were going flying, with all our gear, complete pre-flight briefing, complete pre-flight of the airplane, etc. After engine start, our instructor led us from the VT-30 line to the run-up area. We followed along, spreading the wings. Once there, we went through all the checks of prop, mags, hydraulics and such. Then he led us on a taxi-around tour of NAS Corpus Christi, looking not unlike elephants on parade, so we could get a feel for what it was like with the tail wheel locked and then unlocked, making turns, etc.

The final part of that first "flight" was that each of us taxied  onto the runway and when we got permission for "takeoff", we held the brakes, stick full back, and ran the R-3350 up to 30" of manifold pressure. Then we released the brakes and without adding power, got a little feel for how much right rudder it took to keep the nose pointed straight down the runway. I don't remember how fast we actually got—enough to get the tail light, anyhow—before we aborted the takeoff and discovered how much left rudder it took to maintain directional control. Then we taxied back to the line, folded the wings, and went through the shutdown procedures. We probably spent 45 minutes or so from start to finish.

Our first real flight was the next day and lasted about two hours, terminating in one landing. The following day, FAM-2 was spent on landing practice: my logbook shows I made 11 landings that consisted of 10 touch-and-goes and one full stop. The third flight was the same and the fourth one was six touch-and-goes and a full stop. The airplane was a beautiful flying machine but it took a little getting used to landing and directional control. By the way, we three-pointed the landings; the bird was heavy enough that it stayed where it was planted.

That was it for "basic fam" but of course we learned a little more with each successive flight. Those four Fam flights were followed by two formation hops, three Tac/Acro flights, and then we got into weapons delivery, day and night navigation, night formation, instruments, and finally FCLP (Field Carrier Landing Practice) and CQ (Carrier Qualification at sea). Total AD flights in my logbook at VT-30 were 44 with no incompletes or repeats.

Monday, August 31, 2015

The Gutless Cutlass?

Some airplanes just don't get any respect. The Vought F7U Cutlass suffers worse than most: "Ensign Killer", "the engines put out less heat than Westinghouse's toasters", "Gutless Cutlass", and so forth. And then there's the iconic photos and video of the VF-124 F7U-3 ramp strike:
Yes, that is the LSO sprinting across the deck to get out of the way, which he did. Contrary to what's reported in various places on the interweb, he wasn't hurt and there were no serious injuries to anyone else on deck. The pilot was killed.

In fact, the F7U-3 had about the same thrust-to-weight ratio as its contemporaries, the F9F-8 Cougar and the FJ-3 Fury, albeit in afterburner. And that's even though Westinghouse did not meet the original engine-thrust specification. The real engine problem was that "dry" engine thrust was only 2/3s of thrust in afterburner and using afterburner involved the burning of prodigious amounts of fuel, significantly limiting range and endurance.

This reliance on afterburner for "full" power would not have been quite so evident but for the fact that the Cutlass lacked a horizontal tail. It therefore required a big, thick wing for low-speed lift since no horizontal tail meant no wing flaps. This is a comparison of the F7U-1 (the F7U-3 wing was basically the same planform) and the F-86.

As a result, at low speed on a low, flat approach to an axial deck carrier, pulling the stick back to increase angle of attack actually decreased lift initially. The subsequent increase in lift was accompanied by a very large increase in drag. From the flight manual: "To change angle of attack alone results in excessive loss of altitude, and the rate of descent is so difficult to control as to preclude safe answering of altitude correction signals from the Landing Signal Officer."

So to recover from being low or settling meant adding thrust, preferably even before the pilot got low or settling began. Unfortunately, the relatively low military thrust and high drag at the angle of attack required to attain a low approach speed meant there wasn't much excess thrust unless the afterburner was used. Which was problematical with the early afterburners. From the flight manual again: "Because increases in angle of attack from flight conditions such as making a turn, stopping a rate of descent, and initiating a climb increases the drag, caution should be exercised to assure that the airplane is accelerating prior to entering the afore-mentioned maneuvers. (A waveoff) must be initiated relatively early because selection of (afterburner) is accompanied by a thrust delay lasting up to two seconds. For the first three seconds following power increase, better airplane acceleration is attained in military power; after three seconds a marked acceleration advantage is obtained in (afterburner)."

The horrific F7U-3 ramp strike was actually preceded by a routine approach and landing. The accident investigation determined that the airplane was above the maximum approach weight when it crashed, which meant it was even heavier on the first, successful, landing. However, on the second approach the pilot got low and was slow to respond to the LSO's "come on" signals.

The multiple incidences of nose gear failure (including a fatal one) were in part due to not wanting to get low and slow on approach. The appearance of being high and fast therefore tended to result in a dive for the deck at the cut, with the result being a nose-wheel first touchdown with excessive sink.
The last Cutlass deployment in the heaviest one, the missile-armed F7U-3M, was on an angled-deck carrier with a descending approach rather than a flat one. There were no incidents.

Ironically, the F8U Crusader's handling qualities on approach were at least as challenging as the F7U's and its accident rate not much better even though it only deployed on angle-deck carriers. However, supersonic performance combined with outstanding endurance meant it was revered instead of reviled and ridiculed.

Saturday, July 18, 2015

Post-War Eastern TBM Variants

25 July 2015: Added  background information on the TBM-3P
19 July 2015: Updated with additions, corrections, and other changes.

Rick Morgan (http://rickmorganbooks.com/index.html) and I have continued to explore the poorly documented post-war history of the various variants of the Eastern Aircraft TBM-3. The Navy still had lots of them after the war. Since they were big and easily modified, they were readily adaptable to other missions besides torpedo, glide, and level bombing that were their raison d'etre.

Most were modified from TBM-3Es. In most cases, the addition of the E would simply mean the addition of electronic equipment, in this case provisions for carrying the APS-4 radar on a stores pylon under the right wing. However, the designation is also associated, possibly coincidentally, with a redesign by Eastern to reduce weight by a few hundred pounds. One of those changes was probably the location of the tailhook, which had been internally housed on all TBFs and prior TBM production. Most TBM-3Es delivered from Eastern probably had the external tailhook. This is an example.

There is evidence that the weight reduction effectivity in production was not the same as for the APS-4 provisions. As a result, the first production -3Es did not have the external tailhook. It is also possible, even likely, that TBM-3s were subsequently modified to the E configuration (i.e. APS-4 provisions) at Navy repair and overhaul facilities but retained the internal tailhook.

Based on the information provided on Joe Baugher's invaluable listing of Bureau Numbers (see http://www.joebaugher.com/navy_serials/navyserials.html) and elsewhere, it appears that one TBM-3E production lot used a block of Bureau Numbers from a cancelled BuAer contract:

Bureau Numbers                 Mfg Number                Model

22857-23656                       1-800                            TBM-3

68062-69538                       801-2277                      TBM-3

85459-86292                       2278-3111 (834)           TBM-3E

53050-53949                       3112-4011 (900)           TBM-3E

91107-91752                       4012-4657 (646)           TBM-3E

These out-of-sequence BuNos explain why many "older" TBM-3s, i.e. with 53XXX BuNos, are configured with an external tailhook even though its effectivity reportedly occurred at either BuNo 85566 or 86175.

For sure there are TBM-3Es with the APS-4 radar and an internal tailhook. In his comment below, Pablo Montero provided a link to this example, which is reportedly a VMTB-234 Avenger circa 1945. It looks like there is an E at the end of the type designation on the vertical fin but as is frequently the case, the BuNo cannot be read.

The next interesting issue is the alphabet soup of TBM-3 variants. A suffix was used when a change was "major" and intended to be permanent, with occasional exceptions (see TBM-3J below). Some are well known:

TBM-3D: A late-war modification to add an APS-3 radar hard mounted on the right wing and ECM (Electronic Counter Measure) equipment. The gun and associated hardware was removed from the turret and the lower compartment by VT(N)-90  to reduce weight since its primary mission was night attack.
TBM-3W: A late-war modification to add an APS-20 radar in a large belly-mounted radome for airborne early warning. Some were converted from TBM-3s like 89471 so it had an internal tailhook.

Some were converted from TBM-3Es like 53894 so it had an external tailhook.

TBM-3R: A Korean War-era modification for COD (Carrier On-board Delivery); see http://tailhooktopics.blogspot.com/2013/01/tbm-3r-cod.html

TBM-3S: A post-war modification to remove the defensive armament and add ASW mission equipment. It was teamed with a TBM-3W variant to provide submarine hunter-killer capability as a placeholder for the AF Guardian. There were variations in the mission equipment and the canopy modification (one was designated TBM-3S2 to distinguish it from the 3S). Note that a crewman now occupies the compartment aft of the pilot.

TBM-3U: A TBM-3 modified to tow targets and for general utility use.
Note that BuNo 69400 was probably delivered from Eastern as a -3 and subsequently modified to carry an APS-4 radar pod under the right wing.

Less well known and sometimes misidentified are the TBM-3N (see http://thanlont.blogspot.com/2015/07/tbm-3n-versus-tbm-3q.html) and TBM-3Q (see http://rickmorganbooks.com/tbm-3q-avenger.html). For example, as Rick points out in his excellent post on the latter, it did not have a belly-mounted radome like the TBM-3W as usually stated in TBM books and online summaries.

And then there are the TBM variants for which we have yet to find documentation, much less photographs. Through the magic of copy and paste, these are identified on many web sites as follows:

TBM-3H: TBM-3 modified for surface search radar

TBM-3J: TBM-3 equipped for all-weather operations (i.e., with wing and tail surface deicing)

TBM-3L: TBM-3 equipped with a retractable searchlight in bomb bay

TBM-3M: TBM-3 conversion as missile launcher

TBM-3P: TBM-3 conversion for photo-reconnaissance

Of these five, for sure the TBM-3P and TBM-3L are correctly identified per Navy documentation dated November 1944.

The TBM-3P was a TBM-3 "equipped with a trimetregon (sic) camera". Rick Morgan has found "less than 10" in CASU (Carrier Aircraft Service Units) pools in San Diego and Pearl Harbor in the 1946 Allowance Lists (some are listed as TBM-3EP, which suggests that "TBM-3Ps" were converted from TBM-3s). CASUs were repair and maintenance centers at some naval air stations; they were also a storage point for airplanes that could be issued to squadrons to replace attrition. The trimetrogon camera installation actually utilized three cameras, left and right oblique and vertical, taking pictures simultaneously. This is the installation in a B-17 (see https://historicairphotos.wordpress.com/2014/05/21/trimetrogon-photography/)
The pictures overlapped so they provided complete coverage from side to side.
The TBM-3P camera installation was probably located in the lower (radioman's) compartment. Since mapping, as opposed to strike-damage assessment, was not a primary air-group mission, the TBM-3P was probably little utilized and appears to have had a short career. No pictures of one have been identified as such.

The same document lists the TBM-3L as a "TBM-3, 3D, or 3E equipped with a searchlight mounted in the bomb bay". Note that the TBM-3D had provisions for a searchlight mounted on a pylon under the left stub wing but since this was "detachable", the suffix L did not apply. (In any event, utilizing the bomb bay for this purpose seems counterproductive, which may be why there aren't too many pictures of the type—I have yet to see one.)

The description of each of the other three TBM variants is dubious. A Navy History and Heritage Command document (HERE) does not list the H and the M and identifies the J as a "utility plane".

At the time, the suffix H was used to designate an airplane modified to be a "hospital", i.e. to transport wounded personnel. That's a possibility, although no TBM-3Hs have been identified. There was reportedly a modification of the TBM-3W's radar to optimize it for submarine-snorkel detection but this would have, if anything, probably resulted in a modification to the existing designation (there is a TBM-3W2, for example).

There may have been TBMs with deice boots but they were not designated TBM-3Js. These were TBMs modified with provisions for target towing, the forerunner of the TBM-3U. However, they retained the carrier-basing and ordnance capability; as a result, the designation of a TBM with this capability depended on whether the tow equipment was installed or not! See the June 1947 issue of Naval Aviation News. The TBM-3U had a permanently installed tow reel and all offensive and defensive mission equipment removed.

The TBM-3M, if there were any, was more likely a modification for weather reconnaissance like the PB4Y-2M, which was the purpose of the suffix at the time. None have been identified.

On the other hand, there are a couple of TBM modifications that we have pictures of but little or no additional information. The first is something in the bomb bay of  TBM-3E BuNo 91704 in a picture provided by Jim Hawkins via Steve Ginter. It looks like there is an opening at the bottom of the aft end of the pod and what might be static discharge wicks or antennas on the bottom of the pod. It could be an early ECM pod installed on this TBM for inflight testing.

Another is a TBM marked as a -3E, reportedly BuNo 69465 at Pax River on 18 January 1946, provided by Jim Sullivan (the TT on the cowling indicates that it was assigned to the Tactical Test division at the time). It was reportedly an attempt by Eastern to compete with the new single-seat BT—soon to be changed to A for attack—airplanes from Douglas, Martin, et al.

Saturday, July 11, 2015

TBM-3N versus the TBM-3Q

I was recently asked if I had any pictures of a TBM-3Q. First, I had to refresh my memory of the type, one of several modifications of TBM-3Es, a veritable alphabet soup of repurposed Turkeys.

The TBM-3E was the last production model, redesigned in detail to reduce weight and add provisions for an APS-4 radar pod under the starboard wing.  The Eastern Aircraft Division of General Motors built 1,480 as the war was winding down and Navy contractors were completing the development of various single-engine attack airplanes like the AD Skyraider that would replace it and the Curtiss SB2C. The most obvious external difference was that the tailhook was stowed under the aft fuselage rather than within it.

The TBM-3Q was one of the first carrier-based airplanes configured specifically for electronic reconnaissance although it retained its ordnance-delivery capability so ELINT (short for electronic intelligence) was more of a collateral duty. It could also be used to "home-in" on enemy ships and shore-based defenses that utilized radar and jam the capability.

I found this picture of two "TBM-3Ns" on the excellent web site of the National Naval Aviation Museum (http://www.navalaviationmuseum.org/).

I thought that they were actually TBM-3Qs because they did not have turrets (according to one online description of the TBM-3Q, a characteristic of this conversion) and had ECM (Electronic Counter Measure) antennas identical to those on the Martin AM-1Q and the various Douglas Skyraider Qs.
I so informed the museum's library staff and got the immediate and polite response that to the best of their knowledge, the Ns did not have a turret and the Qs did. Another strike against online research.

The TBM-3N Radar Operator's position:

It appears that the TBM-3N was a postwar -3E modification to perform night and all-weather attack missions with updated electronic countermeasure avionics as a placeholder for the forthcoming Skyraider. Rick Morgan looked at some postwar location lists and estimates that no more than 30 conversions were accomplished. He found that some were assigned to the air groups linked with FDR (CVB-42) and Saipan (CVL-48) in early 1947 and early 1947/8 respectively. However most were operated by the night composite squadrons that provided detachments to deploying air groups, first VCN-1 and -2 and then their successors, VC-3 and -4. (For a brief summary of the role of composite squadrons, see http://thanlont.blogspot.com/2013/12/composite-squadrons-and-detachments.html.) TBM-3Ns were also operated by the two Fleet All-Weather Training Units, the Pacific (the two pictured above, circa 1950) and Atlantic

This is a picture from the files of the National Naval Aviation Museum of a VCN-2 TBM-3N landing on Philippine Sea in 1948.
 Note the lack of a turret.

There was wartime precedence for the removal of the turret for night attack (and in fact, none of the Navy candidates for its postwar carrier-based attack requirements, day or night, had defensive armament). VT-90N removed the turret hardware (but not the enclosure) from its TBM-3D's in late 1944 or early 1945 to lighten them. If you look closely at the turret, you'll see that a crewman is sitting there, sans machine gun.
Note that the -3D was optimized for night attack with an APS-6 radar hard-mounted to the wing and various ECM antennas. Why was it not a -3N? Good question. For my attempt to unravel the World War II Navy airplane designation suffix history, see http://thanlont.blogspot.com/2014/03/navy-aircraft-designation-suffixes-redux.html and the links therein.

So what did the TBM-3Q look like? Larry Webster came up with this picture of one in an old Japanese aviation enthusiasts' magazine.
It has the aft-fuselage antennas like those on the TBM-3N but also retains the turret.

Rick Morgan was also exploring this question as well. His TBM-3Q post that resulted is far more detailed than the one I was coming up with. See http://rickmorganbooks.com/tbm-3q-avenger.html.

Your guess is as good as mine as to why the turret was retained on the -3Q. Mine is that there was a risk that the focus of its intention to collect electronic information for future strike-mission planning might take umbrage at the fact. As it turned out, several unarmed land-based "spy" planes were shot down during ELINT missions. For incidents involving the U.S. Navy, see https://www.nsa.gov/about/_files/cryptologic_heritage/publications/coldwar/dangerous_business.pdf

Rick Morgan opined that they retained the turrets because they were assigned to VT/VA squadrons that were primarily equipped with TBM-3Es that retained the turret. Since they could be assigned to day strikes along with the other Avengers in the squadron, their crews wouldn't want to be be defenseless in that event, much less likely to be singled out initially because of the lack of a turret.

Friday, July 3, 2015

Call Sign Boron?

A couple of people have asked me about the picture of the VA-55 A-4C above. It was reportedly taken at Danang circa 1967 when the squadron was deployed with Constellation.

Although guesses included a call sign, it was a composite-structure test specimen, installed on a fleet aircraft for a evaluation in operational usage.

From the AIAA paper by A.V. Hawley and M. Ashizawa presented in October 1968 (see HERE for a link to the PDF, which was found by Phil Friddell):

"The (A-4) flap was initially selected as a suitable component for obtaining flight experience with boron filaments. The existing production aluminum flap was redesigned utilizing boron skins supported by a full-depth honeycomb core, while retaining some of the basic component aluminum parts for interchangeability reasons. A second flap design, utilizing graphite as the composite reinforcement and developed in accordance with advanced structural element concepts such as molded graphite parts to replace aluminum rib and hinge fittings was developed. The choice of skin layup and core geometry is explained. It is shown to depend not only on the strength and stability of the skin but also on the temperature and pressure conditions that exist during the cure and secondary bonding. Emphasis is placed on the problems encountered during the design and development phases rather than on those which came to light during the final detailed analysis."

The test specimen was prominently identified, in part because of the health hazards presented by boron fibers when they are burned, and since it was non-standard from a repair standpoint. "Boron" was also a reminder that the component, even damaged, was of interest to the Bureau of Aeronautics and its creators.

Aircraft structure incorporating boron composites were subsequently used in the F-14 among other aircraft.

Thursday, June 18, 2015

Back from Space, But Not Home Yet

Jodie Peeler is my go-to person for the Sikorsky SH-3 (H-3) Sea King. She graciously volunteered to be the guest blogger for this post, distilling the information that she's collected over the past two and a half decades on one notable H-3 assignment:

The Sikorsky SH-3 Sea King as Recovery Helicopter by Jodie Peeler

From Scott Carpenter's Mercury mission in May 1962 to the end of the Apollo lunar program in December 1972, every NASA spacecraft crew retrieved by helicopter was recovered by a Sikorsky Sea King (1). The big, twin-turbine Sea King offered additional interior space, more power, more safety and more versatility than the HUS-1s that recovered Alan Shepard and Gus Grissom after their Mercury flights. Besides, it was natural that the Sea King be pressed into service as a recovery helicopter.

Throughout most of NASA's "expendable era," the prime recovery ships were typically anti-submarine warfare carriers (CVS), with Sea King squadrons already part of their air group. Sending a CVS allowed the Navy to provide NASA a large, capable recovery ship without diverting a scarce "big deck." (2) Although an LPH might be pressed into service with an HS detachment aboard for some missions (3), the CVS became the classic recovery ship, immortalized in countless pictures, film clips, and even model kits.

One particular SH-3 itself became an icon. In particular, an SH-3D with the Bureau Number 152711 became a celebrity for its recovery of the first five Apollo flights to the Moon. You may not know the number 152711, but chances are you've seen pictures of "Old 66," a helicopter so famous it even inspired a love song. (4)

Over the years the saga of "Old 66" has been told time and again, and a certain mythology has built up - as have some misconceptions. What follows is my attempt to assemble some things I've learned, based on what I've found in readings and research.


For an Apollo recovery mission, a prime recovery ship embarked eight SH-3A or SH-3D aircraft and associated personnel from the squadron. This provided plenty of aircraft for the recovery mission, as well as spare aircraft in the event one or more had an issue. The aircraft were maintained in excellent condition and logged many hours in simulation exercises (SIMEX) prior to splashdown day. On a typical recovery, four helicopters participated, with one remaining aboard ship ready to go if needed. Each had a four-person aircrew, plus additional personnel as indicated. This is the deployment for Apollo 11 in July 1969:

 - RECOVERY ONE: The prime recovery helicopter, responsible for picking up the astronauts and bringing them back aboard the ship. RECOVERY also carried a NASA flight surgeon, who would make initial assessments of the astronauts once they were aboard; RECOVERY also carried the leader of the Underwater Demolition Team to the recovery site. On flights that observed quarantine protocol, RECOVERY also carried the Biological Isolation Garments (BIGs) and decontamination equipment to the splashdown site.

- SWIM ONE and SWIM TWO: Each carried three Underwater Demolition Team swimmers to the recovery site. These swimmers would secure the spacecraft and assist the astronauts during recovery, then stay with the spacecraft until it was retrieved. On Apollo 11, SWIM TWO deployed its swimmers, while SWIM ONE hovered nearby with its swimmers as a waiting backup. After the astronauts were aboard RECOVERY, SWIM ONE flew wing with RECOVERY back to the recovery ship as a precaution, while SWIM TWO "babysat" the spacecraft and swimmers until the PRS arrived. (5)

- PHOTO ONE: Carried two cameramen to capture still and motion picture images of the recovery operation. Live television capability became possible starting with Apollo 13 in April 1970. (6)

- In addition, SWIM THREE, with a crew of four plus a UDT swimmer, stood by aboard the recovery ship ready to go if needed. - Recovery ships with fixed-wing capability also launched two Grumman E-1 Tracers, one to serve as on-scene commander (call sign AIR BOSS) while another (call sign RELAY) relayed on-scene communications back to the task force headquarters in Hawaii. (7)


In spite of what has been written elsewhere, none of the SH-3s used by HS units for spacecraft recovery were purpose-built rescue helicopters. They were on temporary duty from their normal ASW/SAR mission, and none of the aircraft were specialized rescue aircraft. (This changed starting with Apollo 15, when recovery duty became the task of HC-1 and its SH-3Gs.) (8)

Instead, temporary modifications were made to the SH-3A/SH-3D aircraft used in recovery operations. It became typical to remove the AN/AQS-13 sonar equipment in most of the embarked helicopters and cover the top of the sonar well. (9) This opened up space in the cabin for crewmembers to move around, room for recovery gear, and to provide space for the astronauts and the NASA physician to move around aboard the recovery helicopter.

Removing the sonar also made room for the SARAH (Search and Rescue and Homing) equipment. This system provided a radio-detection system for locating the spacecraft. It used Yagi-type antennas mounted at the top of the port and starboard sponson struts; the first recovery helicopter to sport these antenna was the Gemini 12 recovery helicopter in November 1966. The signals were fed to receivers in the helicopter's cabin, and crewmen could use the signals to direct the pilots toward the spacecraft's location. (10)

Not every aircraft embarked aboard a recovery ship would be modified. Of the eight SH-3Ds embarked aboard USS Yorktown for the Apollo 8 recovery in 1968, six aircraft had their sonar equipment removed, and five of those had SARAH equipment installed. These modifications were performed aboard ship by squadron personnel, using parts supplied to the squadron. (11)

Starting with Apollo 10, the recovery helicopter was equipped with an uprighting sling made of half-inch nylon line. One end of the sling was attached to a weapons shackle; the other end was taped in place below the starboard cabin door. If the command module was apex-down (Stable II) after splashdown, a helicopter crewman could lower the free end of the sling to a swimmer in the water, who would attach the sling to the spacecraft. The helicopter could then pull the spacecraft over to upright (Stable I) position. (12)

Other modifications to the prime recovery helicopter included installation of photo and film cameras on the starboard side. Two 70mm motion picture cameras and a 35mm still camera were carried on a specially-made mount on the starboard aft weapons position, and at least one camera was mounted on the starboard side between the sponson and the fuselage that was used to take this picture of Apollo 13 Astronaut Jack Swigert.
These cameras were pointed down to capture images of the recovery operation that could be analyzed after the mission. These supplemented the still photos and motion pictures captured by the PHOTO helicopter.

The cameras mounted on recovery helicopters had no capability to transmit live television pictures. Television audiences were limited to what the cameras aboard the recovery ship could see. Live television direct from the recovery scene did not happen until Apollo 13 in 1970, when a live television relay from the PHOTO helicopter finally became a reality. (13)


Bureau Number 152711 (Sikorsky serial number 61-377) was constructed as an SH-3D and completed on March 4, 1967. It appears to have spent its entire career with the "Black Knights" of HS-4.

At this point I have not found out why 152711 was selected as prime recovery helicopter for Apollo 8; perhaps it was the aircraft in best condition, the squadron CO's preferred aircraft, that its side number—66—had a certain something, or just luck of the draw. Regardless, it was 152711 that brought the astronauts aboard Yorktown on December 27, 1968, as live television from the recovery ship presented the historic moment to a worldwide audience.

As it happened, 152711 was also used for the Apollo 10, 11, 12, and 13 recoveries. By late 1969, even though it had received a different, three-digit side number, for the Apollo 12 mission that was painted out and replaced with "66"!

For a online gallery of pictures from the Apollo 11 recovery at the USS Hornet Museum web site, see http://usshornetmuseum.org/PhotoGallery/gallery.php?galleryFolder=1969_CVS_12_Apollo_11

The USS Hornet Museum staff has also posted a gallery for the Apollo 12 recovery: http://usshornetmuseum.org/PhotoGallery/gallery.php?galleryFolder=1969_CVS_12_Apollo_12

Although 152711 was repainted and renumbered a few times after its last spacecraft recovery mission, it always bore five Apollo spacecraft symbols on both sides of the nose.

Old 66 was reportedly slated to be presented to the Smithsonian Institution when after it was no longer needed by the Navy. Unfortunately, it did not survive to be so honored for its prominent role in the Apollo program. On 4 June 1975, during a night training mission using its dipping sonar, 152711 crashed into the ocean off NALF Imperial Beach, California and sank. All four crewmen were rescued although the pilot subsequently died of his injuries.

At the time of the accident, 152711 had logged 3,245.2 flight hours and flown from at least seven aircraft carriers and helicopter landing craft. Although there has been interest in locating and raising it for restoration, the effort and expense of doing so from 800 fathoms deep have so far been prohibitive.

At least three SH-3s now on display have been repainted to resemble "Old 66".  Two of these aircraft, BuNo 148999 aboard Hornet (http://www.uss-hornet.org/) and BuNo 149006 in the Evergreen Aviation Museum(http://evergreenmuseum.org/), are themselves actual recovery helicopters, Gemini 4 and 7 respectively. (148999 was repainted for the 1995 motion picture Apollo 13.) The third is BuNo 149711 aboard Midway in San Diego.


1. Several spaceflights ended with the astronauts coming aboard the recovery ship by means other than helicopter. This includes Mercury 6, Mercury 8, Mercury 9, Gemini 6A, Gemini 8, Gemini 9, all three Skylab missions, and the Apollo-Soyuz Test Project. This was sometimes due to the spacecraft being retrieved by a smaller backup recovery ship; other times, it was because the spacecraft landed close enough to the carrier. The long duration of the Skylab missions meant keeping the astronauts aboard the spacecraft until it was aboard ship was a safer move.

2. One myth that will not die is that USS John F. Kennedy was to have recovered Apollo 11 in order to honor the late President who sent us to the Moon, but that President Nixon vetoed this plan for political reasons. In reality, diverting JFK from the Atlantic Fleet to the Pacific just for the recovery mission would have been a logistical and operational nightmare, impractical for many reasons. Correspondence between CNO Thomas Moorer and NASA Administrator George Mueller details that a CVS was chosen over an LPH because the CVS was a more prestigious ship for such a high-profile mission. Hornet herself was selected because she was readily available; had been training for related missions; was more capable than an LPH; and would not have diverted a larger carrier from duty off Vietnam. The historical record more than justifies Hornet's selection, as ship, crew and squadrons performed magnificently on a challenging mission.

3. Missions recovered by an LPH included Gemini 10 (USS Guadalcanal, with HS-3 detachment), Gemini 11 (USS Guam, with HS-3 detachment), Apollo 9 (USS Guadalcanal, with HS-3 detachment), Apollo 10 (USS Princeton, with HS-4 detachment), Apollo 13 (USS Iwo Jima, with HS-4 detachment), and Apollo 14 (USS New Orleans, with HS-6 detachment). In addition, an HC-1 detachment with SH-3Gs was deployed aboard USS Okinawa for Apollo 15, and aboard USS New Orleans for its three recoveries during the Skylab and Apollo-Soyuz era. Gemini 8 would have been retrieved by USS Boxer had the mission gone as planned.

4. The lyrics for "Helicopter U.S. Navy 66" may be read here, among other places: http://www.songcoleta.com/lyrics/helicopter_us_navy_%2766_%28samantha%29

5. Several accounts tell the story of how SWIM TWO got the call, including Scott Carmichael's "Moon Men Return: USS Hornet and the Recovery of the Apollo 11 Astronauts" (Naval Institute Press, 2011), p. 178-183. Live TV coverage of the Apollo 11 recovery also shows SWIM ONE flying RECOVERY's wing on the way back to Hornet.

6. The live coverage of the Apollo 13 splashdown, with plenty of live video from the photo helicopter, may be seen starting here: https://www.youtube.com/watch?v=swTUBotqTRk

7. Much of this is adapted from Bob Fish, "Hornet Plus Three: The Story of the Apollo 11 Recovery" (Creative Minds Press, 2010), p. 107.

8. Al Adcock's "H-3 Sea King In Action" (Squadron/Signal Publications, 1995) implies that the SH-3s that recovered Apollo astronauts were specialized SAR variants. However, multiple sources from the period confirm the SH-3A and SH-3D aircraft from HS squadrons were fully-capable sub hunters whose primary mission was antisubmarine warfare. Had it not been, there would have been no need to remove the dipping sonar from these aircraft; and had it not been, 152711 would have not crashed during a night ASW training exercise in 1975.

9. Removal of the AN/AQS-13 equipment and installation of the SARAH equipment is mentioned in the HS-4 summary from USS Yorktown's Apollo 8 post-recovery report, provided to the author by the Naval Historical Center.

10. The first mission with Yagi-equipped recovery helicopters was the Gemini 12 recovery in November 1966, as can be seen in contemporary photos and films of the recovery. Details on the SARAH installation aboard the helicopters comes from Fish, p. 79-80.

11. USS Yorktown Apollo 8 post-recovery report.

12. Fish, p. 80.

13. Ben Kocivar's article "Waiting for Apollo 13" in the August 1970 "Popular Science" mentions the live television from the recovery scene: https://books.google.com/books?id=kgEAAAAAMBAJ&lpg=PP1&pg=PA44