Israel Retires the Skyhawk

After 48 years and 263 airframes, the IDF has this week finally retired the mighty A-4 Skyhawk.

[youtube https://www.youtube.com/watch?v=lRTF7jWJh1Q]

That leaves Argentina, Brazil and Singapore* as the remaining users.

*Well, arguably the US still uses it, as Draken International contracts to provide services to the Navy and Air Force.

New Zealand Skyhawks

When the A4D-1 Skyhawk first entered service with the US Navy and Marine Corps, it was simple almost to the point of crudity. For instance, to pare down the weight, it didn’t even have a battery. External power carts were needed to start the aircraft. The only “sophisticated” avionics on board was the AJB-3 computer used for the delivery of nuclear weapons. A combination of an attitude indicator and  crude analog computer, it guided a Skyhawk pilot through an “idiot loop” over the shoulder toss. It was good enough for nukes, but nowhere near precise enough for conventional weapons. Regular bombs and rockets were delivered using essentially the same aiming technology as a World War II dive bomber or fighter.

Later models of the Skyhawk introduced air-to-ground radar, but even that was more an aid to navigation than anything else, and weapons delivery was still contingent upon clear skies and an ability to actually see the target. And again, the actual delivery was made using the  same techniques as in World War II.

This lack of precision delivery avionics explains why Argentinian A-4B and A-4C aircraft had to press their attacks on British warships in the Falklands to insanely close ranges, to the point where their fuses didn’t have enough time to arm.

Eventually, digital computers would find their way into modern avionics. One nifty tool that quickly gained popularity was the Continuously Computed Impact Point mode. A digital computer would assess the attitude of the aircraft, its airspeed, known winds, type of ordnance selected, and altitude, and predict the impact point. As the mode implies, that process is updated continuously. It made visual dive bombing much, much easier, and much more accurate.

Updating older aircraft to take advantage of these new systems, and new smart weapons such as the Maverick missile, became a very popular option, especially for smaller air forces. And one of the smallest air forces was the Royal New Zealand Air Force. The RNZAF had operated 10 A-4K Skyhawks (essentially an A-4F with minor changes) since the 1970s. In 1986, they began an upgrade program that included the installation of the APG-66 radar (used in the F-16A) and other modern avionics, including the ability to fire the Maverick missile, the 1000 pound GBU-16 laser guided bomb,* and the AIM-9L Sidewinder missile. Known as Project KAHU, the upgraded Skyhawk was a formidable little jet, and the success of the project is evident by the subsequent upgrade of surplus A-4Ms to A-4AR standard for Argentina.

[youtube https://www.youtube.com/watch?v=HOks35Yhhps]

In 1998, the New Zealand government finally decided to replace the A-4 with the F-16, but in 2001 a newly installed liberal Labour government cancelled that plan, and instead decided to drop the combat mission from the RNZAF, leaving it with just transport and maritime patrol capabilities.

The KAHU Skyhawks were retired into long term storage until 2011, when they were bought by Draken International. Today they serve as contract adversary aircraft supporting US Navy and Air Force training.

http://www.drakenintl.com/uploads/2014/08/about/04.jpg

*It could carry and drop the bomb, but had no designation capability. That laser designation would have to be provided by a controller on the ground, or an allied aircraft.

The Skyhawk soldiers on.

Spill tipped me to this.  The US Air Force has contracted with Draken to provide adversary support to F-35 operational testing at Edwards AFB.

8/27/2015 – EDWARDS AIR FORCE BASE, Calif. — A-4 Skyhawks have taken to the skies over Edwards in support of operational test of the F-35A for the Royal Netherlands Air Force. They are part of a tactics development and evaluation exercise initiated by the 323nd Test and Evaluation Squadron and supported by the Joint Strike Fighter Operational Test Team from Aug. 17-28.
“Each service and each country has their own specific test events that they want to test for themselves, for their own service and their own country requirements,” said Rich Radvanyi, JOTT Planning Cell chief.
The JOTT has five operational test squadrons composed of the 31st Test and Evaluation Squadron, the Marines’ VMX-22 squadron, the United Kingdom squadron 17(R), the Dutch 323nd Test and Evaluation Squadron and Navy squadron VX-9.

Draken

Much as Lex worked with ATAC providing Kfir’s and Hunters to the Navy as contract adversary support, Draken offers jets as needed to the Air Force (and other customers).

The Draken Skyhawks have an interesting history. Built as A-4Ks for the Royal New Zealand Air Force as a slight variant of the A-4F, they were later upgraded with the APG-66 radar (same as the F-16A) and avionics allowing the use of precision guided weapons. But in 2001, New Zealand decided they no longer needed jet combat aircraft, and retired their Skyhawk fleet. Having a good radar aboard allows the Draken Skyhawks to provide a sophisticated threat profile in exercises, beyond that of most other contract aircraft.

Sixty-one years after Ed Heinemann’s Hot Rod first took to the skies, the Skyhawk still soldiers on in active service with Brazil, Argentina, Singapore and until this year, Israel. That’s one hell of a record for a combat aircraft.

MERs and TERs.

This is the AD-6 Skyraider.

http://www.skytamer.com/1.2/2006/6138.jpg

You’ll notice in addition to four 20mm cannon, it has three large weapon stations, and twelve smaller ones along the wing and under the centerline.

That meant it could carry quite a few weapons. The AD-6 was used by the Navy primarily as a medium attack platform. The other prime operator of the Skyraider in the 1950s, the US Marine Corps, used it primarily as a Close Air Support (CAS) platform.  The large number of weapon stations helped it excel at the mission.

But by the late 1950s, the AD series was clearly becoming obsolete, and the the replacement for the Skyraider, the light attack A4D-2/2N (later, A-4B/C Skyhawk) was entering service to replace it in both US Navy and Marine Corps service.  As an aside, while designing the Skyhawk, Ed Heineman also designed a new series of conventional bombs to go with it.

The Skyhawk is rightly revered as one of the best light attack aircraft ever designed. Indeed, it’s still in frontline service in Argentina! But in its earliest incarnation, a bright young Marine test pilot realized it wasn’t much of a CAS platform. It flew well, and could bomb accurately. It just didn’t carry much.

https://c2.staticflickr.com/8/7256/6877313996_5b911fe3de_z.jpg

The A4D-2 and A4D-2N only had three weapon stations. That meant a total of, at most, three bombs. For the Navy, that wasn’t a huge issue. They envisioned using the Skyhawk in the nuclear strike role. Two drop tanks, as seen above, and a nuclear weapon on the centerline station was just what they had asked for.

But our bright young Marine test pilot, correctly guessing that future wars were more likely to resemble the recently concluded Korean War than Armageddon, sought a way to improve the Skyhawk as a conventional bomber. And the answer was, why not hang more than one bomb on a station? A simple steel rack and cabling harness would be the interface between one pylon, and six bombs.

Captain Fitch set about designing just such a Multiple Carriage Bomb Rack.

The Aero 20 pylon on each A4D-2 wing and the Aero 7 centerline pylon were part of the basic aircraft and were installed at the factory. The MCBR for the A4D-2 would simply attach to each of those pylons. The wiring system for the MCBR would be set up so that if the need arose during an emergency, you could jettison the MCBR with its bombs attached. That jettison would be accomplished by firing the secondary cartridge within either the Aero 7A or Area 20. With the MCBR attached to a pylon, the primary cartridge within the Aero 7 or Aero 20 would never be hooked up. Talking with the VX-5 avionics officer, he said that the wiring system for the MCBR could be done by VX-5 avionics with a simple wiring harness to be installed in the MCBR. . I had told him that the MC BR on the Aero 7A pylon would have six (6) HE or inert bombs attached to it. While at first I thought that there could be six (6) HE or inert bombs on each A4D-2 wing station MCBR, interference of the wheel well door would dictate that there would be only five (5) bombs for the wing MCBR.. All bombs on the MCBR would be suspended independent of the other bombs on the MCBR, using the Aero-15 racks from a crashed AD Skyraider.

Fitch even received the patent for his design.

Eventually, Fitch’s rather crude design would be improved, and produced as the Multiple Ejector Rack, or MER, capable of carrying six Mk82 500lb bombs. A similar Triple Ejector Rack could carry three Mk83 1000lb bomb, or three Mk82s.

By using MERs, and A4D-2 suddenly went from carry three bombs to as many as 16.* And it wasn’t just the Skyhawk that benefited. Virtually every tactical aircraft in the Navy, and soon the Air Force, would be carrying bombs in multiples of three or six.

http://cdn.globalaircraft.org/media/img/planes/lowres/a-6_2.jpg

Instead of just five bombs…

The widespread use of precision guided munitions has actually lead to the near demise of the MER. Whereas before a strike plane might carry a load of, say, a dozen Mk82 bombs, today that same strike plane might only carry two or four JDAM bombs, mated directly to the parent pylon.

But Fitch’s story of innovation and the support he received to develop a low cost solution to a problem the service didn’t even really know it had, should serve as a lesson to today’s leadership of how to empower junior officers.

*Because of weapons clearance issues with the gear doors, the MERs on the wing stations could only carry five weapons apiece.

The Army’s Quest for its Own CAS – Part 2

Looking back again at the the Army’s efforts to develop a close air support (CAS) capability during the Cold War.  As mentioned in the first post, in the mid-1950s the Army considered an organic fixed-wing CAS resource but remained constrained by policy.  Skirting the rules in some ways, the Army first stepped up development of helicopters.  When further constraints limited those options, the Army considered jet powered forward air controllers (FAC) as an option.  After testing the T-37 trainer jets, the Army acquiesced to Air Force pressure, but continued to pursue the FAC/recon requirement in at least three separate attempts.   Now I have never seen indications that Army leaders purposely set out to “wear down” the Air Force, or for that matter even deliberately attempted to evolve FACs into a CAS capability through some deception.  But considering that many airframes tested from 1961 to 1966 were plumbed to carry advanced weaponry, perhaps someone from the Army’s side of the E-Ring had some grand plans.

The first attempt at a credible combat jet came in 1960 when the Army, citing a capabilities shortfall, announced a test program for a fast FAC and tactical reconnaissance platform. In 1961, those tests included two Douglas A4D-2N Skyhawks, two Fiat G.91Rs, and a Northrop N-156F.

The Skyhawks came from Navy stocks, differing from standard production with double wheel main landing gear. Of course in 1961 the A-4 (as it was later re-designated) was already becoming a classic aircraft in the hands of Navy aviators and Marines.

Germany loaned two Fiat G.91s, then just entering service as the new “standard” NATO attack jet of the period. The jet was designed from the start with forward airbases in mind.  Unfortunately, during tests at Fort Rucker in 1961, one of the two Fiat jets crashed.

The Northrop N-156F was a fighter derivative from the Air Force’s T-38 supersonic trainer, also just then entering full service. The lone N-156F was one of two tested – but rejected – by the Air Force.  The N-156F offered many advanced construction techniques. But of most interest to the Army, Northrop incorporated many features to simplify field maintenance, to include easy engine removal.

The Army’s tests at Fort Rucker continued through 1962.  But under pressure from the Air Force, the Army abandoned any follow-up requirements and returned all the surviving jets.  Normally I’d detail the particulars for each of these jets, comparing performance and weapons loads.  But since none of these progressed beyond testing, the numbers are only useful for hypothetical discussions.  However, I’d be remiss not mentioning the subsequent service histories of these three types.

The A-4 earned an enviable reputation over Vietnam as a agile, reliable and rugged attack aircraft.  The “Scooter’s” faced the most imposing air defenses ever deployed (both over Hanoi and the Middle East) and survived.  Like it predecessor, the A-1 (or AD) Skyraider, the A-4 carried an impressive warload, enabling many modifications and enhancements over the years.

The Fiat G.91 remains somewhat overshadowed on this side of the Atlantic.  The type sat on NATO’s front lines for some thirty-five years.  But their only combat service occurred in the hands of Portuguese pilots in African colonial actions. Yet the G.91s also earned a solid record of reliable peacetime service in several allied air forces.

Having lost both initial Air Force interest and the Army’s attention, Northrop persisted with the N-156F.  The project received a reprieve in 1962 when President Kennedy, with an eye to arming allies, directed the Air Force to develop a low-cost alternative to the “century series” fighters.  The resulting F-5A differed in a few details from the prototypes.  Over the next forty years the F-5 armed many NATO and allied nations (and remains out there to this day).  But operationally the US Air Force flew only a token force, mostly to prove the type’s validity in front line service.  US F-5s saw more use as dissimilar aggressor opponents for both Air Force and Navy training programs.

Thus all three of the aircraft tested by the Army in 1961 served long and successful careers – but not in US Army colors.  Had the Army purchased any of the three types in quantity, no doubt the airframes would have served with distinction.  If there was a fault in the evaluated types, it was their similarity to Air Force fighter jets of the day.

But concurrent to these attack jet tests, the Army was pursuing a radical concept that greatly differed from the Air Force’s fighter jets – VTOL.  I’ll discuss that next.