Saturday, December 10, 2016

Horses for Courses: Intruder vs. Buccaneer

If you're familiar with both U.S. Navy and Royal Navy airplane programs from the early 1960s, you may have wondered why the former developed a bigish carrier-based, subsonic, two-seat attack airplane when the latter already had one in development, the Blackburn Buccaneer:
Via Tony Buttler

Certainly the U.S. Navy was paying close attention to the Royal Navy during the early 1950s when the Buccaneer program was initiated, as evidenced by its adoption of the steam catapult, the angled deck, and the mirror-landing system.

The answer is basically requirements. The U.S. Navy wanted a replacement for the obsolescent Douglas AD-5N Skyraider that it and the Marines used for all-weather attack and to a limited extent, antisubmarine warfare.

Some of the requirements overlapped, for example range, payload, carrier-compatibility. However, the Navy wanted to be able to find and accurately bomb a land target while the Brits had in mind a strike against ships at sea or naval bases. As a result, the Buccaneer was optimized for near-sonic speed at sea level for a survivable run-in against a heavily armed target: tandem cockpits, a small radar dish (but adequate to find a big target), an internal bomb bay, a relatively small wing, a retractable inflight refueling probe (also see comment below), and unusually for a subsonic airplane, area ruling. The Intruder, on the other hand, had not one but two radars, side-by-side seating (not a handicap given the size of the nose required for the radars) five stores pylons, a relatively high-aspect-ratio wing (required in part for the Marines desire for short takeoffs and landing ashore), etc. It was definitely not area ruled and its refueling probe was always extended.

For more on the development of U.S. Navy attack airplanes including the A-6, see my book, Strike from the Sea, available from Specialty Press or Amazon (https://www.amazon.com/Strike-Sea-Aircraft-Skyraider-1948-Present/dp/1580071325):


Note that there are other books with the same title...

Friday, September 30, 2016

The Turtle's Takeoff



Great googly moogly...

For a summary description of this Lockheed P2V's record distance flight, see http://thanlont.blogspot.com/2011/01/truculent-turtle.html

I knew the overloaded takeoff from Perth, Australia was a close-run thing, but I just came across this video recently posted by Ken Horner:

https://www.youtube.com/watch?v=8cyQklgmfzE

Note that for maximum takeoff benefit from JATO, you fire the rockets so that burnout occurs just after liftoff. That is why there is no JATO boost during the first part of the takeoff roll.

In the event of an engine failure at or above 1,000 feet after takeoff, the crew had a fuel-jettison plan (including getting rid of the tip tanks) to get down to a weight that would allow them to climb before they hit the ground. It doesn't look like they got to 1,000 feet for a while...

Thursday, September 29, 2016

How Hard is It to Land on an Aircraft Carrier?

U.S. Navy Mass Communication Specialist 3rd Class Tomas Compian

I was recently asked "How hard is it to land on an aircraft carrier?" I regret to say that I don't know personally. My only pilot experience in that regard is making an approach and landing a Lockheed S-3 in a Navy flight simulator. My only actual carrier landing was as self-loading freight facing backwards in the cabin of a Grumman C-2 Greyhound transport. (I can say in that case there was an unsettling amount of flight control activity and throttle changes on short final before a very firm arrival and impressively short stop.)

However, I have a lot of second-hand knowledge based on reading books/articles, an overnight stay on an aircraft carrier being used for day and night carrier qualifications, listening to naval aviators, etc. The degree of difficulty also depends on the era. In the beginning, landing speeds were much slower and crashes less dramatic, at least as far as the pilots were concerned. As airplanes got bigger and heavier, higher landing speeds were required and crashes became much more colorful. The introduction of jets reached the upper limit of practicality and the Navy was in danger of exceeding it.

The angled deck and the mirror-landing concept were adopted just in time to restore a reasonable amount of repeatability to the landing process. (The fact that carriers were getting bigger and bigger was also beneficial.) The latest automated landing systems now being qualified promise to make the carrier landing a non-event, the equivalent of the self-driving car.

For the time being, however, a carrier landing requires a high degree of precision with potentially fatal consequences for getting it wrong, similar to a high-wire circus act without a net or safety harness. The precision required is akin to flying under a low bridge, a high-risk and foolhardy maneuver. Hitting the bridge, its supports on either side, or the water is likely to be fatal.

The penalty for being too high in the event of a carrier landing is not fatal but means not being able to land on that approach. Another is required, prolonging the time the carrier has to spend on that course and potentially delaying the subsequent launch cycle.

Being a bit too far off to the left or right on a carrier landing is almost as bad as hitting the bridge supports. It risks a crash into parked airplanes on either side of the landing area and/or going off the deck into the water.
 U.S. Navy Mass Communication Specialist 3rd Class Rob Aylward

Being too low is the worst, resulting in a ramp strike. A bit too low might just mean damaging the tail hook, which requires a diversion to a shore base or a landing on the carrier using the barricade which again disrupts carrier operations. Hitting the ramp with the airplane itself is frequently fatal.


How big is the opening? About 20 feet by 20 feet. The target height for the end of the tail hook at the target angle of descent is about 14 feet above the ramp. Being only four feet or so higher means missing the last wire and having to take off again, a bolter.

The width of the opening is constrained by the imperative to keep either wingtip safely distant from the "foul line" that other airplanes and equipment are kept behind. In other words, the naval aviator can touch down as much as 10 feet on either side of the center line as long as the sideward drift, if any, is toward the center line and not away from it.

However, simple passing through the imaginary opening about 20 feet high and 20 feet wide is not sufficient. At that instant the airplane must also be traveling at the target airspeed and with the target rate of descent so as to put the tailhook on the deck between the second and third wires. Being too fast or at too shallow a rate of descent means touching down beyond the last of the four wires and boltering; too high a rate of descent, while insuring that the hook touches the deck before the last wire, risks exceeding the strength of the landing gear.
 The resulting ejection was successful.
 U.S. Navy Photographer's Mate Louis J. Cera

It helps that the target rate of descent, while high—about eight knots or nine miles per hour—is not much more than one third of the demonstrated capability of the landing gear. Landing gear strength is one of several differentiators between airplanes designed for carrier operations versus those that fly from airfields. The stronger landing gear means that the naval aviator does not have to, in fact should not, flare to decrease the rate of descent as part of the landing because not flaring increases touchdown accuracy.

It doesn't help that a lot of time is not allowed to get lined up with the opening and stabilized at the target airspeed and rate of descent. There is often a compelling reason to get all the airplanes aboard in as short a time as possible (for one thing, the carrier has to be headed into the wind for landings and that may very well not be the direction that the battle group needs to go). As a result, the time allotted for the final approach is on 15 to 18 seconds in daytime.

Moreover, unlike an opening under a bridge, the one that the naval aviator must pass through is moving. Even the biggest carriers are affected by stormy or ocean-swell conditions: depending on the sea state, a carrier can move in six different ways—pitch, roll, yaw, heave, sway, and surge—in various combinations. Although the ship movement isn’t quite random, it is not really predictable either. The current big-deck carriers, at least, don’t move quite as much as the smaller ones did.
The rate of change of a big-deck carrier from one extreme to another is also usually relatively slow. Nevertheless, under certain sea conditions, the ramp can move about 20 feet, the height of the imaginary opening, or more in only 10 seconds.

There is also the added degree of difficulty of having to fly "under the bridge" at night from time to time, with only a few lights as guidance as to the location of the opening. As a result, the final approach is then lengthened to about 25 seconds.

For dramatic video of carrier landings under those conditions, watch these:
 https://www.youtube.com/watch?v=4gGMI8d3vLs
https://www.youtube.com/watch?v=S0yj70QbBzg

Although the naval aviator is alone in the cockpit, he or she is assisted by the advice and counsel of a Landing Signal Officer (LSO) standing on the deck who monitors the approach and can often detect an unacceptable trend developing with it or with carrier motion before the aviator does. The LSO's command to abandon the attempt, a wave off, must be complied with.

Tom Wolf in his book, The Right Stuff, observed that test pilots and race car drivers are not preternaturally brave or foolhardy but instead have convinced themselves that they have the skill and knowledge to not crash as opposed to those who have. Prospective naval aviators go through a training program that is designed to instill that level of confidence in them. It also ruthlessly eliminates individuals potentially inadequate to the task. (For more on this, see my book, Training the Right Stuff, HERE.)

The naval aviator prowess at carrier landing continues to be closely monitored during his career by the LSOs, squadron commanders, and the Carrier Wing Commander for poor performance at sea. The result is a very low crash and casualty rate in what is widely regarded as the most demanding aviator skill, the carrier landing.

Friday, July 15, 2016

McDonnell XFD-1 Phantom First Flight - One Engine or Two?

It's widely reported or at least implied that the U.S. Navy's first jet airplane, the twin-engine McDonnell XFD-1 Phantom, made its first flight on 26 January 1945 with only one engine installed. Unfortunately, no picture of that momentous event appears to exist, probably because of wartime secrecy. The following picture is of the second XFD-1, which was used for the at-sea carrier trials (you can just see some of the Davis barrier actuation framework in place ahead of the windscreen), and taken some months later.

My fairly well-informed assessment is that this story is apocryphal and resulted from the conflation of two separate events:
1) Early January 1945 high-speed taxi testing at St. Louis with only one engine installed because only one was available. Accomplished prior to an actual up-and-away flight, these are baby steps to evaluate control response, stability (albeit in ground effect), acceleration, braking and steering effectiveness, etc. On at least one of these test runs down the runway the Phantom was briefly airborne, which is not uncommon but certainly does not constitute a flight as it is generally understood.
2) An actual first flight with two engines installed on 26 January 1945.

The single-engine taxi test culminating in a "hop" is documented except for the date. In an article in the September 1946 issue of Aviation, Kendall Perkins (at that time McDonnell's Assistant Chief Engineer) wrote "the first plane, after a number of preliminary tests, made its initial hop (rising a short way off the ground) before the second engine had been installed." In 1981 he gave a presentation on "McDonnell's First Phantom" to the Aeronautical History Society of St. Louis during which he said:

"Well anyway, we flew the airplane in I think it was January of '45, was (sic) the first time. The one interesting, unusual thing about the first flight was that some people didn't even call it a first flight. We took it out of the hangar and we only had one engine at that time. We couldn't get delivery on a second engine, but we were so impatient to get started on taxi testing that we said, well we can taxi it on one engine so we just left a big hole on the other side and taxied it out on the runway and ran it up for a few hundred yards and taxied it back and ran it up a few hundred yards more and it wasn't long before he just took it off the ground. Actually it flew about half way down the runway on just one engine. I don't know whether that a longer flight than the first Wright brothers flight but I suspect it was."

In an undated paper*, "Developmental History of the McDonnell FD-1 or FH-1 Phantom", prepared by the Historian's Office in the Naval Air Systems Command, Washington, D.C. the author(s) wrote:

"(The 19B) engine performed well enough in the October (1944) tests to be delivered to the McDonnell plant, but the XFD-1 needed two engines and only one was on hand; a second was simply unavailable due to technical difficulties. As a result, McDonnell engineers had to be content with installing the single engine and conducting taxi tests at their plant. The second engine finally arrived, and on 26 January 1945 the XFD-1 flew for the first time. The aircraft flew twice that day for a total flight time of 49 minutes."

It seems likely that the author(s) would have used primary sources when writing this paragraph.

An online Phantom summary that doesn't reference primary sources but seems to be credible and provides specific dates: http://tanks45.tripod.com/Jets45/Histories/FH-1/FH-1.htm

In summary, it states that the single-engine "hop" was accomplished on 2 January 1945 with a second engine arriving on 4 January. It was installed for the first flight accomplished by Woodward Burke on 26 January. It also states the flight time on that date as 49 minutes, which is clearly more than a hop.

I'm still hoping that someone comes up with McDonnell test reports from January 1945 that documents whether the up-and-away first flight, as opposed to the "hop", was on one engine or two.

*One of the end notes references a book published in 1972.

Wednesday, July 13, 2016

A History of the Northrop Corporation's Projects


The title and subtitle pretty much summarize the contents in this excellent Specialty Press publication authored by long-time Northrop employee Tony Chong. And a wonderful collection of drawings, illustrations, and pictures it is, tied together with a narrative describing the ups and downs of Northrop over six decades of rapidly changing aerospace technology. Many of the projects described never progressed very far after being created by the predesign group but they provide a comprehensive sense of the company's changing and evolving raison d'etre and business fortunes.

Why recommend this book in a U.S. Navy Aircraft History blog? The answer is that Northrop proposed or considered proposing on Navy programs many times, almost all of which are probably described here. Although Northrop was never successful in that regard, not counting its contribution to the genesis of the F-18, those projects (several of which were new to me) provide a fresh and fascinating look at the Navy's aircraft mission requirements and program competitions over the years.

The book also illustrates the function of an aircraft company's preliminary design department, which is not only to respond to company marketing but also to explore new configurations and concepts for not only existing markets and requirements but those not yet defined or acknowledged. Most go unrequited but the process always has the potential for new business.




Friday, June 24, 2016

Training the Right Stuff

Amazon is shipping my latest book, coauthored with Mark Frankel, now.
"A comprehensive study of the training aircraft used to transition the United States military into the jet age. At the end of World War II, high-performance jets with unfamiliar operating characteristics were replacing propeller-driven airplanes. As accident rates soared, the Air Force and Navy recognized the need to develop new trainers to introduce fledgling as well as experienced pilots to jet flight. The first step occurred in 1948, when a two-seat jet trainer, the T-33, was developed with private funds. It was welcomed by the Air Force and subsequently the Navy, allowing both services to start building modern air arms. Over time other new trainers were developed to serve specific needs while innovations, such as high fidelity simulators, accelerated the process, reduced costs, and increased safety. The evolution continues today with the goal of producing high-quality newly winged aviators for assignment to operational squadrons."

Sunday, June 5, 2016

It Now Takes All the Running You Can Do To Keep in the Same Place

https://news.usni.org/2016/05/26/navy-lays-bare-fa-18-readiness-gaps-take-year-surge-air-wing

Once upon a time, the Navy had the luxury of margin in its airplane inventory. In the mid-1950s, an air group might have three fighter squadrons or even four assigned to it. Since it would usually deploy on a carrier with only two, that meant the one left behind could be transitioning to a new type, which occurred much more often in those days.

Up until then, these squadrons were only assigned "day" fighters. All-weather fighters were provided to the air group for a deployment by so-called composite squadron as detachments (see http://thanlont.blogspot.com/2013/12/composite-squadrons-and-detachments.html). That was beginning to change however.

Carrier Air Group One is an example. For its history, see this excellent monograph by Douglas Olson and Angelo Romano:
It is regrettably out of print and no longer available from the publisher, but try and find it elsewhere.

CVG-1 was blessed with four fighter squadrons in 1953. One of them, VF-11, the Red Rippers, began a transition to the Douglas F3D Skyknight in August. Note the very colorful red trim of the first squadron.

Prior to this, this big, two-man, three-radar, twin-engine all-weather fighter was only assigned to composite squadrons VC-3 and -4 and Marine all-weather squadrons. However, they proved to be unpopular aboard the carriers and only VC-4 made a handful of deployments. One of them culminated in the F3Ds (and their crews) being offloaded to a Marine night fighter squadron during the Korean War, where they were welcomed with open arms.

The Navy therefore decided to reequip VF-11 with its newest all-weather fighter, the single-seat F2H-4 for CVG-1's next deployment. That transition began in December 1953. Its 14 Skyknights were transferred to a sister squadron, VF-14, the Top Hatters, beginning in January, replacing its obsolete F4U-4 Corsairs, and introducing its pilots to the jet age.

As it happened, the number of Navy carrier air groups was set by Congress. However, the surge and operating tempo of the Korean war had required more than that number so the Navy created Air Task Groups, which "borrowed" squadrons from existing air groups for a deployment.  (See http://www.navalaviationfoundation.org/archive/sfl/sflshow.php?id=9085.) ATG-201 was formed up in June 1954 with one of its squadrons being VF-14, deemed surplus to CVG-1's immediate requirement. It retained its 4xx side number and yellow trim. The tail code was amended to be ATG.

VF-14 participated in an ATG-201 workup aboard Intrepid in October/November 1954.
(Note that the A and G have not been added to the T on the wing.)

However, when the time came for ATG-201 to deploy with Bennington in 1955, it was with CVG-1's VF-13 flying F9F-8 day fighters instead. The all-weather fighter capability was provided by a VC-4 detachment of F2H-4s.

Nevertheless, VF-14 continued to fly F3Ds through mid-1956 with CVG-1, reverting back to just T for the tail code (note the over-paint of the other letters on the fin), here bringing a high-ranking Defense Department official aboard Forrestal.

VF-14 did not, however, deploy with CVG-1 either while flying the Skyknight. After it transitioned to the F3H-2N Demon, it finally deployed with Forrestal in 1957, ending a four-year hiatus.




Friday, May 27, 2016

Grumman Stoof and Stoof with a Roof Monograph

Part 2 of Steve Ginter's series on the S2F and its variants is now available:

It was written by Doug Siegfried and Steve Ginter. (Bob Kowalski and I wrote Part 1. See http://thanlont.blogspot.com/2016/01/grumman-s2fs-2-tracker-monograph.html)

In 249 pages, Part 2 provides a summary history, heavily illustrated, of U.S military squadrons when they operated the S2F/S-2 and the WF-2/E-1B. That includes Marines, reserves, test, training, stations, etc. You can buy it directly from Steve here: http://www.ginterbooks.com/NAVAL/NF102.htm

But wait, there's more! Part 3 will cover the TF-1/C-1A.

I really didn't make any contribution to this volume other than a picture on page 50. That's me standing between VS-21's LT John Brandenburg and my brother, John Gregory, then in diapers. The picture was taken by my stepfather, George Gregory, then the deputy Public Works Officer at NAS Sangley Point in the Philippine Islands (see http://thanlont.blogspot.com/2013/07/halcyon-days-v.html). Here's another:

Tuesday, May 3, 2016

Power Steering

The U.S. Navy carrier-based jets did not initially have nose-wheel steering. The reason at the time was that implementation was thought to restrict the turning radius, a critical capability for deck parking and taxiing onto and off of a deck-edge elevator.

Judicious use of power and brakes was used instead. A tiller bar slipped over or into the nose wheel axle was sometimes used to provide more precise steering by a deck hand.
The deck crew would also sometimes just push on one side of a forward fuselage to help align the airplane with the catapult or for parking.

The free-castering of the nose wheel could sometimes result in an incident. This AJ was launched with the nose wheel facing aft. As a result, the nose landing gear jammed so it could not be fully retracted.

However, that did not preclude carrying on with the assigned mission. The nose wheel would almost always recenter on landing without drama. Some air groups had the right side of the AJ's nose wheel painted white to insure that the Savage was catapulted with it properly aligned.

One of the changes that the Navy made to the Air Force's T-34 when it procured it for training was the removal of nose-wheel steering so that its aviators would learn to taxi without it.

The F7U-3 is reportedly the first Navy carrier-based jet with nose-wheel steering. It was big, it was heavy, and the forward fuselage was too far above the ground to be used for alignment by several sailors. Note the tiller bar.

The actuator was added to the landing gear scissors. On most airplanes, a button on the stick grip enabled steering via the rudder pedals.
Most, if not all carrier-based airplanes were equipped with nose-wheel steering thereafter. In fact, later models of the A-4 Skyhawk, beginning with the TA-4, were equipped with it, probably to provide better crosswind takeoff and landing capability.
However, it reportedly did not provide fine-enough steering control for lining up with the catapult track. As a result, the tiller bar was often employed.

One problem with that was the risk of the pilot absentmindedly employing his nose-gear steering when the tiller was attached. It was then a large and very powerful bat. As a result, some A-4 squadrons removed nose-gear steering for a deployment. Also see Jeff Brown's report here: http://thanlont.blogspot.com/2011/11/scooter-stuff.html

Carriers have gotten bigger but the need for excellent steering control remains.
U.S. Navy photo by Mass Communication Specialist 3rd Class Joshua Card

Monday, March 7, 2016

The Westinghouse J40 Engine Program

The rise and fall of the Westinghouse Aviation Gas Turbine Division is a fascinating story, worthy of being a Harvard Business School case. I posted a summary here: http://thanlont.blogspot.com/2011/03/from-hero-to-zero.html and have also written about it in my books, Air Superiority and Strike From the Sea. However for the complete story on the fiasco that was the Navy's J40 engine program, this is the book, available from Amazon where you will see two five-star reviews and also at Barnes & Noble as well as overseas distributors.:

 Fair warning: it's detailed, technical, and comprehensive even by my standards, literally a blow-by-blow description of the engine and its development, down to the level of individual parts. There is relatively limited discussion of the airplanes it powered and the difficulties it caused in their development.

Nevertheless,  if you have significant interest in early 1950s U.S. Navy jet fighter programs, this is a book to have. I particularly appreciate that—unlike the usual publication for aviation enthusiasts that relies on the content of previous books and articles on the subject and obvious (and too frequently wrong) internet posts—Paul has taken the time and trouble to find and incorporate information from primary sources at the Smithsonian Air and Space Museum, the National Archives, and the Hagley Museum and Library, among others.

My understanding is that Paul is currently writing a similar history on the Westinghouse J46, which was only marginally more successful than the J40. I look forward to it with great anticipation.

Sunday, February 21, 2016

Tailhook Design Redux

I've updated the original "Brief History" post with an additional example and some minor rewording:
http://thanlont.blogspot.com/2011/12/brief-history-of-tailhook-design.html

Friday, February 12, 2016

A3D Skywarrior Bombardier/Navigator

Paul Bless suggested the following article from the October 1959 issue of Naval Aviation News as a companion piece to the preceding post on the A3D third crewman.
To read it, simply click on the image to view it. Right click on the resulting image to "View Image". There should then be a magnifying glass with a + sign that you can click on to get an even bigger image.

Saturday, February 6, 2016

A3D Skywarrior Third Crewman

From Naval Aviation New, May 1960:
Note that "weaponeer" was the crew member assigned to arm a nuclear weapon after takeoff. Navy officers had this responsibility on the Hiroshima and Nagasaki missions.

Paul Bless provided more information on the individuals listed above: Shelly and Szeller were misspellings; their last names were Skelly and Szeyller.  Greenwood and Skelly went on to become A3D bombardier/navigators (see the Naval Enlisted Bombardier/Navigator Association website). Szeyller became one of the first F4H RIOs and was killed in a midair collision with another F-4 in 1967.

Friday, January 22, 2016

In Memory of Ensign Raymond Hite, Jr.



 Ensign Raymond Maxwell Hite, Jr was killed on 18 May 1961 in the crash of the first Sageburner attempt to set the record for “speed over a straight three-kilometer course at a restricted altitude” with the McDonnell F4H Phantom II. This involved making four passes, two in each direction, at an altitude above the ground of no more than 100 meters (328 feet). Hite was the Radar Intercept Officer in the rear cockpit.

Most accounts of the accident (including, I regret to report, my own) only mention the pilot, Commander Jack L. Felsman. At some point early on, Hite’s presence began to be overlooked, which is lamentable because he was the epitome of Tom Brokaw’s “Greatest Generation” and arguably critical to the success of the record-breaking attempt because of his ability to use the F4H’s radar to coach the pilot onto the course, not easily seen visually from an altitude of only 100 feet at supersonic speed.

In 1942, when he was only 14 but big and mature for his years, he enlisted in the Army Air Corps. Before his true age was discovered and he was discharged, he had flown combat missions as a gunner in a Martin B-26 and shot down a German fighter. At 17, he joined the Navy, initially serving as a gunner on a patrol bomber.

In 1952, he was selected for training as an enlisted Bombardier/Navigator. This was not unusual at the time but becoming rare. It had been a natural transition of enlisted men from gunners/radiomen to radar operators to bombardiers. However, by the late 1950s, following the introduction of the Douglas A3D Skywarrior, almost all Navy bombardier/navigators were officers.

As reported in one of his commendations, he won the top individual honors by a wide margin in Heavy Attack Wing One’s Sixth Bombing Derby held in December 1958: “The competition tested performance in bombing, celestial and radar navigation, and a thorough understanding of special weapons in addition to normal crew duties and understanding of aircraft systems.”

In part as a result, Hite was selected to be an officer and commissioned as an Ensign in January 1960. His new assignment as a Limited Duty Officer, Aviation Ordnance, was to be part of the A3J-1 Vigilante test program as bombardier/navigator. His new duty station was the U.S. Naval Air Special Weapons Facility at Kirtland Air Force Base, Albuquerque, New Mexico.

In addition to the A3J testing, Hite participated in the evaluation of the Navy’s newest fighter, the Phantom II, that also had a nuclear weapon delivery capability including radar mapping for navigation.

Hite had already survived two horrific Navy carrier-based bomber accidents, bailing out of an AJ Savage that had lost its vertical fin and an A3D Skywarrior after an explosion severed its aft fuselage. Unfortunately, he and Felsman had no chance to escape this one. The Navy investigation attributed the crash to an unsuspected pitch-damper failure, the slowness of the existing pitch-trim system, Felsman's abrupt last-moment maneuver to line up on the record course, and the susceptibility of the F4H to Pilot-Induced Oscillation (PIO) at transonic speed and low altitude. PIO occurs when the airplane’s dynamic response to an externally generated (e.g. turbulence) pitch change matches that of the pilot’s response to it. If both airplane and pilot then react, again simultaneously, to the larger than expected pitch change, hell’s-own roller-coaster ride results. If the pilot doesn’t take himself out of the loop, i.e. let go of or not move the stick, the result could be an overload of the airplane’s structure.

When I joined McDonnell in 1966 as a flight test engineer fresh out of college, I was shown the then closely held movie clip of the inflight breakup of the first Sageburner. The pitch excursions didn’t seem particularly large but within a few seconds and about three cycles, ended with the airplane disintegrating at 14 gs, well above its design structural limit, and the engines flying out of the debris headed down course. It is now a video on YouTube.

Raymond Hite left a pregnant wife and three daughters bereft that day. He deserves to be remembered for the moment that ended his almost 20 years of service to his country.

Tuesday, January 5, 2016

Grumman S2F/S-2 Tracker Monograph


Finally (it's been a work-in-progress for a long time). It's currently being printed and should be on Steve Ginter's website (http://www.ginterbooks.com/NAVAL/NAVAL.htm) shortly. My coauthor, Bob Kowalski, was one of the earliest Navy S2F pilots; I got to sit in one with my mother about that same time.

  And in 1993, I got to fly one, courtesy of what is now Cascade Aerospace.

I can assure you that there's stuff in this monograph that you haven't seen before.
In summary:
The Grumman S2F (S-2) was developed to meet a specific mission requirement, carrier-based antisubmarine warfare. It proved to be so useful and adaptable that it is still in military and civil service more than 60 years after it first flew in December 1952. Richly illustrated and personalized by Tracker pilots and crewmen anecdotes, Grumman S2F/S-2 Tracker describes its evolution from initial requirement to eventual replacement including unsuccessful Grumman proposals for improved versions. Its service in foreign militaries and adaptation to wildfire control are also summarized along with descriptions of the Carrier On-board Delivery (COD) and Airborne Early Warning (AEW) variants.

Friday, January 1, 2016

A-6 "Iron Hand" Conversions

Operation Iron Hand was a belated endeavor to deal proactively with Surface to Air Missile (SAM) sites during the Vietnam War. Although construction of the sites was no secret, attacking them was not allowed by the Department of Defense until Navy and Air Force airplanes started being shot down. The first USAF mission in late July 1965 was a total failure, with six of the 46 F-105s being shot down by conventional antiaircraft gun batteries in what turned out to be a strike on a well-protected but SAM-less site.

There were basically three ways to deal with SAMs: evade them; electronically jam or mislead the tracking radar and guidance signals; and destroy the sites. Evading them was iffy and required a visual sighting soon enough to do so. Jamming or misleading the tracking and guidance was only somewhat effective. Destroying the sites with conventional attacks was problematic because they were heavily defended with an array of radar-directed and barrage-type antiaircraft guns.

Another method of destroying the SAM capability was the use of an Anti-Radiation Missile (ARM), which was fired well outside of the SAM site's conventional AAA defenses, homed in on its tracking radar, and destroyed it. The Navy had already developed an ARM using its Sparrow missile combined with a radar-homing seeker. This was designated the AGM-45 Shrike and was usually fired from the Douglas A-4 Skyhawk.

These Navy missions received the nickname Iron Hand after the original operation. (The corresponding USAF aircraft were known as Wild Weasels.)

The only problem was, the Shrike's range was significantly less than that of the Russian SA-2 SAM, making an Iron Hand attack too much of a fair fight. The next ARM was therefore a modification of a big Navy ship-launched Surface-to-Air Missile, which resulted in the AGM-78 Standard ARM. Since it weighed almost 1,400 lbs, it had to be carried by the Grumman A-6 Intruder.

Rick Morgan has written two posts which describe the history of the various A-6 "Iron Hand" derivatives:

http://rickmorganbooks.com/a-6b-standard-arm.html

http://rickmorganbooks.com/a-6e-anawg-21.html