The McDonnell Douglas F-4 Phantom II is a legend. An extremely competent multi-role aircraft it was one of the few planes to serve with the United States Navy, Marines and Air Force, making the Phantom one of the most important types to fly during the Cold War.
Indeed, the Phantom’s widespread service, flying with the air forces and navies of twelve countries, made it the West’s most potent combat aircraft in several strategically important locations and in multiple confrontations over a two-decade period.
In terms of the technical advance the aircraft represented on its introduction into service in 1961, combined with its operational capabilities, the sheer numbers produced and an extensive combat record, the Phantom has a solid claim to being one of the best combat aircraft ever built. Indeed, you’ll find some aviation historians that will argue that the aircraft ranks as the greatest fighter of all time.
Of course, such an aircraft saw a huge amount of development during its service career to be ranked so highly, and the Phantom was continuously upgraded throughout its life span; a period that spans from the aircraft’s first flight in 1958 to the current day. This in an aircraft that ended production in 1979, with a total of 5197 built.
Naturally, with the Phantom being in such widespread service, the end of production did not mean the end of upgrading and development efforts. Though McDonnel Douglas stopped building new models, other nations that relied on the F-4 for their defence did update the design so that it would continue to meet their needs.
But interestingly the United States did not, at least not to anything like the standards other nations planned. Which is a little surprising, given the context.
Though the end of the Cold War ultimately meant that the F-4 could be retired in the 1990s from US service, that hadn’t been the original expectation. As the F-4 was displaced by the newer “teen-series” aircraft at the end of the 1970’s and beginning of the ‘80’s, the expectation was that the Phantom would continue to serve in the US Reserve and National Guard fleets for possibly two more decades.
In fact, in 1983 there were 885 F-4s serving in front line USAF squadrons, with another 649 in the Air National Guard, plus additional hundreds with the Reserves.
And though the United States was purchasing new F-14 and F-18s to replace the F-4 with the Navy and Marine Corps, as well as F-15 and F-16s to do likewise with the Air Force, it was still thought at the time that perhaps as many as four hundred Phantoms could still be serving in the National Guard and Reserves by the year 2000. Of course, by that point they would have been badly out of date.
In fact, with around 2,500 Phantoms serving with US forces and important foreign allies in 1983, the prospect of the Phantom becoming obsolete and still being in widespread service looked entirely likely and a matter of concern. Recognising this prospect, the Department of Defense (DoD) began to mull the possibility of conducting a more thorough overhaul of the Phantoms in service with a view to increasing their long-term viability.
And here they hit a bit of a snag.
The problem they faced was that none of the big US fighter manufacturers wanted the Phantom to survive into anything like the long-term future in US service.
The original builder, McDonnel Douglas, was happily building as many F-15s and F-18s as it could to replace the F-4 in service with the US Air Force, Navy and Marines. Grumman was building F-14s, again the F-4s direct replacement for fleet air defence. And General Dynamics was building the F-16, which would displace the F-4 in its tactical strike role.
All these manufacturers were planning on their new aircraft not just replacing the Phantom, but eventually bringing in newer models that would allow these earlier “Teen-series” aircraft to be replaced themselves in turn where they could fill the National Guard and Reserve squadrons.
The other company that may have been capable of conducting a major update plan was Northrop. But at that time, they were pushing their new F-20 Tigershark extremely hard in a sales attempt to get it adopted in the Air National Guard and Reserve fleets. They also had high hopes of the F-20 becoming a primary export fighter for US allies around the globe, something that a modernised Phantom would jeopardise.
So, it isn’t accurate to say the major fighter builders had a cartel arrangement as regards to a major product improvement on the F-4, but they did all have a vested interest in not seeing it happen. Such an aircraft would draw money from the US defence budget that would otherwise go to buying what was coming off their current production lines, as well as jeopardising prospective foreign export sales.
But this didn’t stop the DoD (primarily in the guise of under-Secretary of Defence for Research and Technology Richard DeLauer) wanting the possibility looked at, and so they turned to a somewhat surprising – at the time – alternative.
Now, Boeing might be a big deal in the field now, but at that point they hadn’t built a fighter aircraft that had seen service since the P-26 “Peashooter”, which first flew in 1932. However, Boeing recognised an opportunity, and in fact had already been acquiring expertise on the F-4.
In June 1983 the Boeing Military Airplane Company (BMAC) had won a contract over rival McDonnell Douglas to overhaul F-4Cs of the Air National Guard and Air Force Reserve.
This saw BMAC overhaul the aircraft thoroughly, and this and the preliminary work they had conducted in preparation of the bid meant that their engineers had as good an understanding of the Phantom as any.
And so, in September 1983, BMAC offered to the DOD the concept for a modernised F-4; The Boeing Super Phantom.
In fact, three options were offered, which would allow customers to customise the Phantoms to as far as their requirements, and wallets, needed.
The first, most basic was to replace the F-4s J79 turbojets with Pratt and Whitney PW1120 turbofans. This brand-new engine, that had only begun full testing a year before, was a cutting edge powerplant that Pratt and Whitney had developed for the Israeli Lavi light fighter project.
The -1120 also had the advantage of having seventy percent commonalty with the F100 engine that was used in the F-15 and F-16. Additionally, Pratt and Whitney had already considered the possibility of fitting the new engine to the F-4 and were keen to assist any builder that wanted to market the match up.
With the new engine fit, the F-4’s performance would have been much improved. In contrast to the J79’s, which produced just under 18,000 lbs of thrust each, the -1120 produced 20,600 lbs. They also weighed a thousand pound less than the older engine.
So, a reengined F-4 would immediately lose nearly a tonne in weight and have around fourteen percent more power. This would have greatly improved the F-4s performance.
A Phantom so equipped would have a Thrust-to-Weight of 1.03 to 1, only marginally below that of the F-15 Eagle and significantly better than that of the major Soviet fighters the aircraft would be expected to encounter. All told this was expected by Boeing to have improved the aircraft’s acceleration and turning circle, making it an even more formidable dogfighter.
It would also have removed the infamous smoke trail that Phantoms produced. Might seem a minor point, but in an air combat fight, visibility and target acquisition are critical and smoky trails have the potential to give away an aircraft’s position.
The second option involved fitting a conformal fuel tank as well as the new engines.
This was based on a 1978 exploratory project that Boeing had conducted for the US Air Force to investigate the possibility of such an addition, and that work was dusted off for the Super Phantom proposal. The tank would have been streamlined into the F-4s belly and been capable to carry 5000 litres (1320 gallons) of fuel.
This would allow the Phantom to dispense with the 2,700 litre belly tank that they generally carried on long missions, but with the benefit of actually carrying a greater fuel load in a far more streamlined profile. Indeed, the conformal tank almost matched the total external drop tankage that F-4s could carry on their fuselage and two inner wing pylons, which was around 6,000 litres.
This meant the Super Phantom could have freed up its two inner pylons for additional weapon carriage in comparison to an original F-4, or else still carried the wing tanks for even greater range. And the conformal tank would still be fitted to carry weapon loads such as Sparrow or the upcoming at the time AMRAAM air-to-air missiles.
It would also have been possible to fit a flare/decoy dispenser into the new fuselage as well, again, a useful combat addition.
One prospective customer for this configuration was Britain’s Royal Air Force, who were using Phantoms for long-range defence of the North Sea and still a few years away from getting their Tornado ADV interceptors that were being built for the role.
The third proposed upgrade option was to completely overhaul the Phantom’s electronic suite to make it as formidable as anything flying at the time. This would have seen the radar switched out from whatever was fitted in the aircraft at the time for the APG-65 that was being fitted to the early models of the F-18 Hornet just then coming into service.
Though this radar seems to have been the preferred option by Boeing (and indeed would eventually be fitted to Phantoms in German and Greek service) they also apparently considered offering the option of fitting the APG-66 that was used on the F-16.
Either of these modern multi-mode radars would have been a considerable improvement on the various old types used on the various F-4 models at the time, offering far superior capabilities and the possibility of integrating with the latest weapons of the day as well as those projected for the future.
Boeing also proposed installing the wide-angle Heads-Up-Display (HUD) used on the F-16, as well as two of the multifunction display screens used by that aircraft, as well as the navigation system and avionics processors used by the F-20.
All of this was combined with a thorough airframe overhaul that would extend the aircraft’s service life by between 2,000 and 3,000 hours. That equates to about ten to fifteen years in front line US service, so maybe a bit longer in National Guard or Reserve use.
And the price of this upgrade? Well, that’s where it all got a bit contentious.
Boeing informed the DoD that they could perform the full upgrade at a cost of seven-to-nine million dollars per aircraft, with cost scaling’s from more conversions pushing the lower price.
The DoD liked that and asked the US Air Force to look at the proposals with a mind to start initial developments work, principally in the fitting of a PW 1120 to an F-4 for trials.
And the USAF basically went “no”. They were not at all happy at the idea of taking aging air frames and reconditioning them. As they put it, an old F-4, even updated, was still an old aircraft.
They also disputed that the cost would come in at $9 million, instead projecting that the price of a Super Phantom would actually be $17 million per unit. As at the time they were buying brand new F-16s at a fly away cost of $13 million, they weren’t inclined to spend money on old planes when they could new ones for less. They also pointed out that every new F-15 and F-16 purchased drove the cost of these, their new current front-line fighters, down further.
So, they were inclined to agree with the manufacturers that export sales of the fighters on the production line would also provide savings on current US military purchase plans, something that upgrading the Phantom would not.
It is difficult to say which side was correct in their assessment. Many Phantom users did transition to “Teen-series” aircraft as their F-4s aged, proving the Air Force correct in that regard. But several operators did, as said, upgrade their Phantoms, turning these last operating stalwarts into even more formidable aircraft.
Had Boeing been given more support, would these conversions have been undertaken in the United States, generating more work for the American defence industry? Possibly.
But ultimately, the Super Phantom vanished into history, another interesting “what-if”
Huge thanks to Mike Lombardi at Boeing for providing me with the information that I used to this article.
Aviation Week & Space Technology; January 9, 1984
Jane’s Defence Weekly; 19 January, 1985