U.S. Navy Aircraft History

By Tommy H. Thomason

Wednesday, January 3, 2018

Pre-war Downward-Vision Windows

One of the interesting features I noticed early on as I grew better acquainted with the history and development of U.S. Navy carrier-based airplanes was the presence of downward vision windows on most of the early monoplanes. My first guess was that they were incorporated to somewhat make up for the reduction in downward visibility resulting from the larger wing located more directly under the pilot. An example is the XF2F-1. As in most of the biplane fighters, the pilot sat just aft of the trailing edge of the lower wing.

The most significant benefit from restoring a view directly downward would be the ability to better judge drift from a crosswind, which would provide better accuracy for the dead reckoning necessary to find your way back to a carrier on an otherwise trackless ocean.

And that would appear to be the case for the downward vision windows in the Brewster F2A Buffalo and the Grumman F4F Wildcat.
Note that the F2A window is huge relative to the F4F's, indicative of a lack of specificity for the requirement. The F4F window was not intended to be used to determine whether the landing gear was down, as some have speculated. The pilot can't see the wheels through the window even when the shock struts are fully extended.
The windows are also of no use in landing. A pilot uses his peripheral vision to judge height above, and position over, the runway and the LSO's signals when landing on a carrier.

My original theory, even if correct, doesn't hold for the bombers since the pilot in the biplanes was generally located over the bottom wing. In any event, the earliest monoplane scout bombers like the BT-1 and SBA don't appear to have had downward-vision windows. The follow-on Brewster SB2A, Douglas SBD Dauntless and its replacement, the Curtiss SB2C Helldiver, did. In this case, they were sometimes referred to as Bombing Approach Windows.

This is the Naval Aviation Museum's SB2A when it was conveniently hung from the ceiling. Note the channels on either side of the window for the struts of the bomb-displacement mechanism.

The SBD's was located just aft of the post for the bomb-displacement mechanism and is hard to see even in this excellent Miles Lombard photo.
 The SB2C's is even more rarely remarked upon. It was ahead of the bomb bay and aft of the oil cooler flaps on the belly. It was covered by doors, which kept the window clean until needed.
 I have yet to see a picture with these doors open. The SB2C-3/4 pilots manual states that they were "removed from the SB2C-4 and replaced with an access panel". That was the end of the use of bombing approach windows.

The monoplane torpedo bombers beginning with the Douglas TBD Devastator had a downward vision window but in this case, it was for use by the bombardier although the pilot could see downward through it as well. The TBD was originally intended to function as a level bomber as well as a torpedo bomber. In fact, the Norden bomb sight made famous by the Army Air Force was initially a U.S. Navy project. The bombardier would crawl underneath the pilots seat from his seat in the center cockpit to use it.
 Two large doors kept the window clean until needed.

The Grumman TBF was originally designed for level bombing using the Norden bomb sight as well,

In the following picture, the window, located above the number "8636", is covered by a protective flap.

The Vought TBU's bombing window and sight were similarly located aft of the bomb bay as well.

The final variation of the downward-vision window was present in the Vought XF4U-1, Grumman XF5F-1, and Bell XFL-1. In this case it was again a bombing window, but for very specific armament, small antiaircraft bombs housed within compartments in the wings.

The requirement also mentioned another purpose for the window:

As it happened, the antiaircraft-bomb requirement was dropped for F4U production (also see http://thanlont.blogspot.com/2008/06/antiaircraft-bombs.html) but the window remained for a time.

Sunday, October 1, 2017

The First Supersonic U.S. Navy Fighter?

That claim is made for the F8U/F-8 Crusader in the subtitle of Bill Spidle's excellent book on its development (see yesterday's post). Some might quibble with that (many think it was the F4D Skyray if the definition is restricted to supersonic in level flight) so I undertook to determine which airplane had supersonic bragging rights.

After World War II, the Navy embarked on an ambitious program to develop high-performance swept-wing jet fighters, contracting for the Vought F7U-1 Cutlass, Douglas F4D Skyray, Grumman F10F Jaguar, and McDonnell F3H Demon. All were intended to have afterburning engines and be supersonic, at least in a dive. The F4D was expected to be supersonic in level flight.

There is no question in my mind that XF7U-1 BuNo 122474 was the first U.S. Navy fighter to break the sound barrier, albeit in a dive and then only to Mach 1.006, on 21 June 1950. And that was with the aid of afterburning.

It was only capable of about Mach 0.9 in level flight. The thrust required as you approach Mach 1, the speed of sound (which varies with air temperature) is significant as depicted, approximately, in this illustration.
Note the dramatic steepening of the curve at about Mach 0.9.

None of the other fighters of its generation (or the F7U-3 for that matter) were capable of staying supersonic in level flight either. The XF10F was never dived faster than Mach 0.975 (for one thing, Grumman was never provided an afterburner for its J40 engine) in a single high-speed test flight on 11 October 1952, five months after its first flight. The sleek XF3H Demon, which first flew in August 1951, was probably the fastest, having been dived to Mach 1.3, but as far as I know, it never broke the sound barrier in level flight and the heavier production Demons were not as fast.

What of the F4D? Douglas projected its top speed would be Mach 1.2 in level flight. Its first flight on 21 January 1951 was with an interim J35 engine. After the more powerful J40 finally became available (without an afterburner), an XF4D was dived through the sound barrier in mid 1952. In October, finally equipped with an afterburner, it set an official absolute speed record on a three-km low-altitude, sea-level course of 753.4 mph. That wasn't, however, supersonic. The speed of sound at 15 degrees C and sea level is 761.1 mph but the successful attempt was made, deliberately so, when the temperature had reached almost 37 degrees C (even though it decreases engine thrust, a higher temperature is your friend when you don't have quite enough thrust to go supersonic in level flight) because that raises the speed at which the transonic drag increase begins. The speed of sound was therefore about 790 mph on the course, which means that the XF4D's speed was about Mach 0.95.

Although Douglas engineers and test pilots strove mightily to reduce the F4D's transonic drag and achieve supersonic speed in level flight, they were unable to do so, as reported by the Navy following its formal acceptance tests in late 1957.

If you restrict claimants to supersonic speed in level flight, there is one other contender, the Grumman F11F Tiger. It was probably the first fighter to be area-ruled by design. Grumman expected it to reach a level flight speed of Mach 1.21. Grumman received "go-ahead" for the program a month before Vought was notified that it had won the OS-130 competition. It first flew, as the F9F-9, on 30 July 1954. However, Grumman didn't receive an afterburner for it until late 1954 or early 1955 and the first attempt to fly supersonically with it on 25 January 1955 was terminated at Mach 1.03 when it failed catastrophically. Wright wasn't able to provide another flight-worthy one for more than a year. In May 1956, the F11F would finally just break the sound barrier in level flight; according to its Standard Aircraft Characteristics Chart, its top speed was Mach 1.1 at 35,000 feet.

Meanwhile, Vought had flown its F8U for the first time on 25 March 1955, breaking the sound barrier in the process, possibly but not necessarily in level flight.

Because of ongoing modifications required to make the F11F suitable for operational use, the F8U was delivered to VX-3, the cognizant Navy Air Development squadron, in December 1956, whereas it didn't receive its first F11F until February 1957. However, deliveries to operational squadrons of both airplanes were made in March 1957 and VX-3 took both aboard for at-sea evaluation in April. In the end, although probably not predicated on the fighters' respective readiness, VF-32 deployed with its F8Us aboard Saratoga on 1 February 1958 while VA-156 with F11Fs didn't go out aboard Shangri-La until 8 March 1958.

So Grumman received a contract for the supersonic F11F a month earlier, flew for the first time several months earlier, went supersonic two months earlier, and then faltered on the back stretch, finally deploying in what amounts to a dead heat. It should also be noted that the F11F was just barely supersonic in level flight, while the F8U was really supersonic. Although when the excellent J79 was substituted for the so-so J65, the F11F could arguably match the F8U in speed and altitude capability...

After all that, I think the edge goes to the Crusader over the Tiger for the first supersonic U.S. Navy fighter but it depends on your definition of what constitutes "first" and it won't be by much.

Saturday, September 30, 2017

Vought F-8 Crusader by William D. Spidle

If you're considering buying this book—and you really should if you have any interest in carrier-based airplanes—note the subtitle. It covers the predesign, proposals, engineering design, test (and tragedy), and marketing (think record-setting) of the Crusader and its derivatives from Vought's vision of a true supersonic carrier-based fighter through their retirement. Look elsewhere if you prefer stories beginning "There I was, upside down, in cloud, on fire, nothing on the clock except the maker's name, when suddenly...". There are several available of that genre on the F-8, whereas there are none about it that go into this level of illustrated detail.

Bill Spidle is uniquely qualified to be the author. He had unfettered access to the Vought archives that were maintained by Vought-retiree volunteers and stuffed with documents, pictures, reports, etc. contributed by Vought employees over time. Rare among company archives (some now jealously guarded and almost unavailable to researchers by the company that had absorbed them), Vought's were accessible. In exchange, he helped review and catalogue the material for several years. As a result, his book incorporates pictures, illustrations, and information not only not previously published but which I had not seen before.

Another point to consider is that it is published by Specialty Press, which is once again adding to its sales catalogue of aviation books. As a result, it is a large format (10 inches square) tome with many color and high-resolution photos printed on heavy, glossy paper, a joy to behold and peruse.

One note on the subtitle: The Navy's First Supersonic Jet Fighter. The first ones to reach the fleet were the swept-wing placeholders for those with afterburners that the U.S. Navy had ordered after World War II, the Cutlass, Skyray, Demon, and Jaguar. Like them, however, the F9F Cougar and FJ-2/3 Fury could only break the sound barrier in a dive. And that includes the F4D Skyray, often cited as the first Navy fighter to be supersonic in level flight. It was stubbornly subsonic except in a dive despite Douglas' best efforts to make it otherwise (more on that in another post). Some might argue that Grumman's F11F Tiger was the Navy's first supersonic fighter in terms of level-flight speed since it was on contract and flew before the F8U Crusader did. However, its initial flight test was without an afterburner, whereas Vought test pilot John Konrad took the F8U supersonic on its very first flight. Moreover, F8Us were delivered to Navy development squadron VX-3 in December 1956 whereas the first F11F did not arrive there until February 1957 after a somewhat protracted development required to make it satisfactory for deployment.

Saturday, August 26, 2017

Brewster F2A Buffalo

I have a soft spot for unappreciated or much maligned aircraft as you could tell from the subjects of most of my monographs, i.e. soft-cover books (see http://tommythomason.com/). I might have written one about the F2A Buffalo except that it was built in some numbers and saw service use, which requires a lot more research and insuring that the expected "war stories" are accurate and representative.

Fortunately, Captain Dann is more ambitious and industrious than I and Steve Ginter continues to be open to publishing monographs on lesser known aircraft. The result is an excellent history of the Buffalo, both the airplane itself and its service life in not only the U.S. Navy but other countries.

As importantly, they had the full support of Jim Maas, who is the go-to guy for Buffalo pictures, drawings, useage, etc.

The result is the most in-depth and complete book on the F2A that we are likely to ever have. The various types are described in detail with copious pictures and illustrations, including development and proposed modifications/improvements. Their usage is summarized by country and squadron and includes first-person commentary. Regardless of the extent of your knowledge of the type, I can all but guarantee that there will be pictures that you have not seen before and information that you did not know. (I was unaware of the one-off "XF2A-4", for example.)

As is customary in Ginter publications on specific types (see http://www.ginterbooks.com/), it concludes with a summary of model kits available. Note that you can buy them directly from him, which will help keep these histories of esoteric subjects coming.

Monday, July 31, 2017

F8U-3 Auxiliary Rocket Engine

One of the options after World War II that the U.S. Navy considered for the defense of the carrier against incoming bombers was the deck-launched interceptor. The performance priority was on rate of climb, which required the highest possible thrust-to-weight ratio at the expense of endurance. (Another desire was the ability to launch with zero wind-over-deck or even a tailwind so a time-consuming turn into the wind wasn't necessary.)

Adding a rocket engine for auxiliary thrust in the takeoff, climb, and acceleration phases was therefore very attractive because of the rocket's thrust relative to its weight and the oxidizer required. The Navy was already utilizing JATO (Jet Assisted Takeoff) for seaplane operation in rough water and carrier takeoffs without the benefit of a catapult. The A3D was JATO-capable for just that reason, to be launched with an atomic bomb even if the carrier's catapults were out of action.

JATO was actually a solid-fuel rocket that didn't provide thrust for very long. What was needed was a liquid-fuel rocket. The ultimate in this regard was an interceptor that was relied on rocket engines only. See http://thanlont.blogspot.com/2012/11/and-now-for-something-completely.html

While this concept wasn't taken up, the addition of rocket engines was a feature during the competition for the fleet air defense fighter that resulted in the F4H Phantom. In fact, BuAer was planning on buying some F8U-3s with an auxiliary rocket engine. This is a ground test installation in an F8U-1's aft fuselage.

Reaction Motors was originally selected by BuAer to provide the 8,000-lb thrust rocket engine that was to be located in a fairing at the base of the vertical fin. The airplane's jet fuel was mixed with an oxidizer, hydrogen peroxide, to provide the thrust. (Some of the F8U-3's fuel tanks had to be dedicated to the oxidizer, reducing endurance.) Unfortunately, there was a tragic accident during the test of this engine at the Naval Air Rocket Test Station in Dover, New Jersey. Glenn Repp provided this summary report.
Reaction Motors was replaced by Aerojet and design work continued at Vought, but the auxiliary rocket concept was abandoned when the F8U-3 lost the fly-off to the F4H-1.

For much more on the F8U-3 program, see my monograph available from Steve Ginter:

Saturday, June 17, 2017

Extravagantly Illustrated and Detailed VQ-2 History!

Click on the image to better see the preorder offer for this cradle-to-grave history of one of the earliest and most  used electronic reconnaissance squadrons, which went in harm's way to obtain the intelligence necessary to minimize harm to those that might have to follow.

This collage illustrates the breath and depth of this monograph from noted naval aviation historian, author, and photographer, Angelo Romano and his coauthor, VQ-2's John Herndon:

Sunday, May 7, 2017

The Short, Tragic Operation of the F-4 Phantom by the Blue Angels

In the process of doing some fact checking on the operation of the F-4 Phantom by the Blue Angels, I discovered that many of the online articles about it are somewhat incorrect, beginning with the statement that it served with them from 1969 to 1974. In fact, the 1973 season was tragically terminated early and the Blues resumed flight demonstrations in early 1974 flying Douglas A-4 Skyhawks.

In 1968, the Grumman F11F Tigers, which had served the Blues well for a decade, were increasingly hard to campaign with. Various alternatives were evaluated, but by chance the seemingly ideal candidate was the so-called lead-nosed F-4J. The F-4J was succeeding the F-4B on the production line in St. Louis. The major changes were the AWG-10 radar and fire control system and the J79-GE-10 engine (the identical dash numbers were coincidental). As it happened, both were government furnished equipment and deliveries were behind schedule. The Navy agreed to let McDonnell complete and deliver the first of the Js with lead ballast in the nose (hence the nickname) and the B's -8 engines. Otherwise the airplanes were identical to the J configuration: removal of the IR detector under the radome, bulged inner wing for the bigger main landing gear tires introduced with the Air Force F-4C, lift improvements introduced late in F-4B production, etc. (see http://tailspintopics.blogspot.com/2012/12/you-cant-tell-phantoms-without-score.html)

There were 18 of these built, five in production block 26 and 13 in production block 27, BuNos 153071-153088. Although the Navy had other non-deployable uses for them, their assignment to the Blues was logical since neither the lack of a radar (which allowed the nose to be used as a baggage compartment) or the slightly lower engine thrust of the -8 engine was a drawback. The only external difference apparent from a -10 powered J was the visible portion of the afterburner nozzle (also see http://tailspintopics.blogspot.com/2012/12/j79-exhaust-nozzles.html).
The difference between the nozzles was more apparent when the engine was running but not in afterburner because of the different way the reduction in area for "dry" thrust was mechanized.

Many modifications were made to convert most of these Js to the Blue Angels configuration. These included installation of the Air Force anti-skid braking system, additional radio and navigation avionics, the smoke system, a gaseous oxygen system, etc. The flight control and throttle systems were also modified to provide more precise control in formation and early activation of afterburning. (Joe Debronski, McAir's chief test pilot at the time, flew a formation flight on the wing of the Blues leader at the time, CDR Bill Wheat, in 1968 as the latter put his F11F through the maneuvers required: "(Bill) had requested that I do this to help me understand the need for changes they wanted in the longitudinal control-feel system".)

Wheat accepted the first of an initial seven Blues F-4Js on 23 December 1968. Twelve of the lead-nose Js were eventually converted to the Blue Angels configuration and flown by them at air shows. Ten of them, plus one of the two replacement, -10 powered, Js were destroyed:
Half were the result of three midair collisions. Although trading paint was not unknown because of the extremely close formation flying that the Blues were famous for, actual collisions resulting in a crash had been rare up until then. However, up until the last midair only one of the crashes had been fatal.

Some internet articles also incorrectly identify the specific Phantoms operated by the Blue Angels. One of my F-4 subject-matter experts, Peter Greengrass, provided the following list based on F-4 Aircraft History Cards and other sources;

153072: Midair with 153081 26 July 1973, Lakehurst, NJ
153075: Fuel exhaustion near El Paso, TX 6 November 1969
153076: Reassigned 25 September 1973
153078: Midair with 153081 19 September 1969 (081 did not crash)
153079: Midair with 153080 and 083 at El Centro, 8 March 1973
153080: Midair with 153079 and 083 at El Centro, 8 March 1973
153081: Midair with 153072 26 July 1973, Lakehurst, NJ
153082: In-flight fire 4 June 1971 at Quonset, RI
153083: Midair with 153079 and 080 at El Centro, 8 March 1973
153084: Reassigned 25 September 1973
153085: Gear-up landing 30 August 1970 at Cedar Rapids, IA
153086: Crashed 14 February 1972 in Superstition Mountains, AZ
153839: Reassigned 25 September 1973
153876: Crashed 8 July 1973 at Lake Charles, LA

Note that 153077 is not on this list although it is sometimes identified as a former Blue Angels F-4J; Peter wrote that it was assigned for its entire service life to NATC, Patuxent River. There were also only two later Js assigned. In this picture of the two solos in formation, the -10 powered F-4J is inverted and the -8 powered one is right side up.

Peter also identified three F-4Bs that were briefly assigned to the Blues early on for training/proficiency/hack duties: 150996, 152982, and 153068. These were stock and did not sport the Blues livery.

1973 was both a triumph and a tragedy for the Blue Angels. It began ominously with a three-plane collision during training in March at El Centro. All three pilots ejected successfully but leader LCDR Don Bently was injured and had to be replaced by former Blue Angel LCDR Skip Umstead. In June, he led them on a multi-venue European tour including performances at the prestigious Paris Air Show. Tragically, he was killed along with Marine CAPT Mike Murphy and Ronald Thomas, one of the two Petty Officers flying with them when they collided during arrival at Lakehurst, NJ for a show.

That disaster ended the Phantoms use by the Blues and the 1973 season. It also almost resulted in the Blues being disbanded but in part due to the support of the Chief of Naval Operations, the team was reformed that winter with Douglas A-4F "Super Fox" Skyhawks (see http://tailspintopics.blogspot.com/2011/02/super-fox.html) that had been made redundant with the introduction of the Vought A-7 Corsair. A successful 1974 season resulted.

For more information on the F-4 Phantom with the Blue Angels, see the following on Ron Downey's excellent blog:

McAir Flight Test Report

Information and Markings