F-14D Tomcat vs. F/18 E/F Super Hornet

Editors Note: Every airplane that goes into service is accompanied by controversy. This is especially true of the F/A-18E/F Super Hornet. Our two experts argue that the Super Hornet is not necessarily the airplane the Navy needs for the future, and their backgrounds lend weight to their arguments. Rear Admiral Paul Gillcrist U.S. Navy (Ret.) spent 33 years as a fighter jet pilot and wing commander and was operations commander for all Pacific Fleet fighters. Bob Kress is an aeronautical engineer and, during his long career at Grumman, he was directly involved in the development of the F-14 Tomcat. Their analysis makes an interesting statement when placed against the background of the war on terrorism.

The requirement for a practical deep interdiction fighter/bomber have long been the subject of controversy within the naval aviation community, especially when it comes to the F-14D Tomcat versus the F/A-18E/F Super Hornet. Often, however, the definition of “deep interdiction” is changed to fit the aircraft carrier under discussion, rather than taking into account the real-world theater of operations for which it is destined.

Events over Afghanistan, however, have forced us to formalize what is really needed if an aircraft is to strike an enemy deep within its country. Today, we know that the politics of surrounding countries can dictate mission distances that stretch the ability of current aircraft to their limits. The U.S. relies on Navy aircraft carriers as bases. So, when putting fighter/bombers over Afghan targets, which aircraft led the charge? – the tried-and-true F-14D Tomcat with the F/A-18 Hornet well behind.

This particular conflict motivated us to address what we see as a serious problem concerning Naval aviation assets and the realities of the fields over which we will fight.

As shown over Afghanistan, there are four basic requirements of any carrier strike force:

Within these four seemingly simple rules are the needs for an airplane to have a long range while carrying sufficient munitions to hammer a target and still be able to fight its way through enemy aircraft and AAA threats.

Because our government isn’t telling us all its secrets, we’ll have to make some assumptions when using Afghanistan as an example. It is, however, obvious that reaching the target presents a great challenge. To avoid Silkworm-class missiles, the carrier battle group probably would not want to venture north of a line joining Masqat, Oman and Ahmadabad, Pakistan. Along this line, the group would be somewhat west of Karachi. Reaching Kabul would require a one-way flight of roughly 825 statute miles. Assuming the use of S-3 tankers, an F-14D strike, refueling somewhere between Quetta and Sukkur, Pakistan, wouldn’t have any trouble attacking targets in the northernmost parts of Afghanistan. If, however, an F/A-18E/F refuels in the same spot, it will barely make it to Kabul. The un-refueled radius of an F-14D carrying the normal strike load (four 2,000 pound LGBs, two Phoenix missiles, and two Sidewinders, plus 675 roundsof 20mm, and two, 280 gallon external tanks) is at least 500 statute miles.

Accompanying E/F Super Hornets have only a 350-statute-mile radius carrying about half the bomb load. To complete the picture of mission distances, the S-3s would have to dash back to the CVs, hot-refuel, and meet the raid coming out of Afghanistan, which would be much in need of JP-4 cocktails.

Why are we nit picking over mission details? Easy! At the beginning of the studies that led to this article, we were convinced that the Afghan campaign would be an all-USAF show, and that would lead to questions of carrier-fleet effectiveness. But map studies combined with knowledge of geopolitical restrictions showed that carrier assets, primarily the F-14D, were just about the U.S.’s only option. This has clearly been substantiated by events.

Of course, the F-14Ds were not the first to hit targets in Afghanistan; b-2 stealth bombers each carried 16, 2,000-pound GPS-guided bombs. The flew from Whiteman AFB in Missouri – a 33-hour round trip. Further, big-time USAF strategic air assets – B-52s and B-1s – arrived shortly afterward.

It was soon apparent that USAF tactical aircraft were not being used in Afghanistan. We found that, even given unlimited in-flight tanker refueling, the USAF F-15 and F-16 could not be used without a Middle Eastern ground base. Turkish bases were simply too far away and would require refueling over hostile areas. Only the use of tactical air bases in Turkmenistan and/or Uzbekistan would work, and this would allow only partial coverage of Afghanistan.

The big question becomes: does the Navy have the assets to able to carry this kind of war into the future, and what kind of planning is in place? To cut to the chase, the discussion once again reverts to whether or not the new Super Hornet will really cut the mustard or the Navy has taken yet another wrong turn that will cost us dearly on the battlefield.

The subject of the erosion of Naval aviation has nagged both of us ever since the cancellation of the A-12 program by the Secretary of Defense in the late ‘80s. It was a watershed for a number of reasons, not the least of which was a level of bad management that hadn’t been seen in the Pentagon for decades! We can look back on that day and clearly see that the unraveling of the fabric of Naval aviation would become a long-term trend. Neither of us contends that the A-12, as envisioned by Navy leaders, was the right airplane to develop at that point in history; in fact, it wasn’t! That, however, is another story for another time.

We have to put off writing this article simply because we know it is likely to ruffle many feathers in the Pentagon and on Capitol Hill, but events in Afghanistan again brought our main arguments into focus. Is writing this kind of article worth it, we wondered; we might be seen to be “piling it on” when the Navy is in difficulty and clearly on a steep, downhill slide. Well, we have listened, with no small restraint, to the pontifications that justify how well the Navy is doing with its favorite program, the F/A-18E/F Super Hornet – despite unimpeachable reports to the contrary from the guys in the fleet; comments made to us by young fleet pilots who have flown the airplane and describe it as “a dog” carry much more weight with us than statements from senior officers and civilians higher in the food chain. But certain pontifications in a statement by a senior Naval officer who should have known better served as the last straw.

The pronouncement appeared along with a spate of triumphal announcements that celebrated the “successful” completion of the Super Hornet’s first operational evaluation (OPEVAL). In a publication called “Inside Washington,” the Navy’s director of operational testing is quoted as saying that the Super Hornet was superior to its earlier models “…in every category but three: acceleration, maximum speed and sustained turning performance.” This pronouncement boggled our minds because these are the very performance capabilities that determine a tactical airplane’s survival. Then, as if to justify this “hand grenade,” the officer is quoted as stating that the Navy has sacrificed speed in the Super Hornet for other beneficial capabilities, and he asserts, “brute speed is no longer the discriminator it once was when the benchmark was the Soviet threat.” It is clear that this Naval officer doesn’t have a clue about aerial combat and the importance of total energy in the complex equation of energy maneuverability. Nor does he seem to understand that Third World countries all around the globe are purchasing the very latest operational Russian-built fighters that are also licensed for production in China. The Russian aerial threat still exists; what has changed is that the pilots aren’t Russians.

As a nation, we have always had the means to protect our own global interests as well as those of other countries. Short of nuclear war, the carrier battle groups have been able to strike on very short notice. A President’s first question in time of crisis is often, “Where are the carriers?”

With a layered defense, including air assets, guided-missile cruisers and frigates and undersea backing, the carrier battle groups are pretty well invulnerable. On the longer Nimitz-class carrier, we see the F14D – a truly long-range fighter/bomber – plus lightweight F/A-18A fighter/bombers. The long-range A-6 bomber has gone forever, but its derivative, the EA-6B Electronic Warfare (EW) aircraft is in place and is in much demand by both the USN and the USAF. This country’s Desert Fox and Kosovo experiences have, at last – and correctly – shifted the focus away from stealth and toward electronic warfare. We will have more to say on this important topic in a subsequent article. In short, at the moment, the deck complement looks adequate. The F-14D can pick up the A-6 role because it was designed to do so from scratch. Its performance in Kosovo as a very effective strike leader has more than borne out that fact. With LANTIRN, night-vision devices and synthetic aperture A/G radar, the F-14 targeted not only its own four 2,000-pound weapons but also the ordinance of the F/A-18s, which don’t have such capable sensors.

An interesting comparison can be made to quantify the F-14D’s strike effectiveness. Compare one F-14D and one B-2 bomber during a two-night (33-hour) mission in Kosovo. In reactive situations (no foreign base), the B-2 operates from the U.S. (lack of overseas B-2 basing is a serious constraint and there are only a limited number of B-2s to begin with). The chart shows the weapons delivered – U.S. to Kosovo and back – for the B-2 and the F-14D.

This simple chart says a great deal about a carrier battle group’s effectiveness. Remember that there are – or there can be – 24 F-14Ds on a ship such as the John C. Stennis (CVN-71). Twenty four F-14Ds can deliver more weapons than the entire 16 aircraft of a B-2 fleet. Unfortunately, the numbers of F-14Ds are dwindling, and they will be almost gone in another 10 years. What will be the replacement?

The F-14D will be replaced by the F/A-18E Super Hornet, which attempts deep-interdiction missions. Though it’s a whizzy little airshow performer with a nice, modern cockpit, it has only 36 percent of the F-14D’s payload/range capability. The F/A-18E Super Hornet has been improved but still has, at best, 50 percent of the F-14D’s capability to deliver a fixed number of bombs (in pounds) on target. This naturally means that the carrier radius of influence drops to 50 percent of what it would have been with the same number of F-14Ds. As a result, the area of influence (not radius) drops 23 percent! No wonder the USN is working on “buddy tanker” versions of the Super Hornet.

By the way, now that the A-6 tanker has gone, how will the Hornets get to deep-interdiction targets?

Contrary to what we’re officially told, a tanker variety of the Hornet is simply not the answer. In an attempt to make it supersonic, the F-18E has been given a low aspect ratio and a razor blade of a wing. This hurts subsonic drag and carrier takeoff payload when compared with the KA-6 tanker, which is an aerodynamically efficient solution. Equally silly is the proposal for an EW version of the F-18E. The same aerodynamic reasons apply for this airplane, plus it has an external stores dilemma. To get sufficient range to support a deep-interdiction mission, the EF-18E would have to use up precious external store stations with fuel tanks rather than ECM pods as carried on the EA-6B. Perhaps the Navy should consider putting the EA-6B back into upgraded and modernized production and build some of them as tankers?

As this is being written, it is too early to comment in an informed manner on the war on terrorism in Afghanistan. The USAF heavy bomber raids are fully public. However, it is evident that USN carrier strike groups that consist of F-14Ds and F-18s are conducting the tactical raids. A study of maps shows that CVN airborne S-3 tankers facilitate the conduct of these raids by refueling, probably over Pakistan. At this time, USAF tactical air assets do not have bases close enough to Afghanistan to allow airborne refueling over friendly nations. By the time this finds its way into print, that may have changed.

Although the Navy has been working very hard to correct F/A-18E/F OPEVAL problems, it is worth summing them up: the production of the F/A-18E/F is significantly overweight with respect to its specifications (30,000 pounds empty weight). This is far in excess of what one would expect for a variant of an existing F/A-18 A, B, C, or D. Aircraft weight estimation methods could, and should, have been much better; in fact, when we look objectively at the F/A-28E/F, we see an airplane with a brand-new wing, new fuselage and new empennage – in other words, a new airplane. This is, therefore, what Congress would call a “new start.” Both Congress and the Department of Defense (DOD) had to be looking the other way when the Navy was permitted to slip this airplane by as a simple modification of an existing airplane.

In combat-maneuvering flight, the aircraft had severe “wing-drop” problems that defied resolution, despite the use of every aerodynamic analytical tool available. Eventually, one test pilot cam up with a “leaky-fold-joint” fix that opened chordwise air slots to aspirate the wing’s upper surface flow and thereby prevent the sharp stalling of one wing before the other. The stalled more or less together, but much easier and more severely than before. This new fix is what the aerodynamicists call a “band aid.” It causes aircraft buffeting, which is generally a source of wing drag. But a “fix” that combined “acceptable” wing drop with “acceptable” buffeting had been achieved. One test pilot commented dryly, “I’d like the buffeting levels to be a little lower so I could read the heads-up display!”

Owing to its high drag and weight (and probably other factors), the F/A-18E is significantly poorer in acceleration than the F/A-18A. Also, its combat ceiling is substantially lower, and its transonic drag rise is very high. We have stayed in touch with some pilots at the Navy’s test center and have gathered some mind boggling anecdotal information. Here are some examples:

An F/A-18A was used to “chase” an F-14D test flight. The F-14D was carrying four 2,000-pound bombs, two 280-gallon drop tanks, two Phoenix missiles and two Sidewinder air-to-air missiles. The chase airplane was in a relatively “clean” configuration with only a centerline fuel tank. At the end of each test flight, the chase airplane was several miles behind the test airplane when the chase airplane reached “bingo” fuel and had to return to base.

An F/A-18E Super Hornet is tested using the same chase airplane, an earlier model Hornet, in the same configuration. The chase airplane does not need full thrust to stay with the test airplane.

An F/A-18E/F in maximum afterburner thrust cannot exceed Mach 1.0 in level flight below 10,000 feet even when it is in the clean configuration (no external stores). At 10,000 feet, the F-14D can exceed Mach 1.6.

A quote from a Hornet pilot is devastatingly frank: “The aircraft is slower than most fighters fielded since the early 1960s.”

The most devastating comment came from a Hornet pilot who flew numerous side-by-side comparison flights with F/A-18E/F Super Hornets and says: “We outran them, we out-flew them and we ran them out of gas. I was embarrassed for them.”

In the January 1991 issue of Naval Aviation, an article reminded us of some history: “After the dive/bomber became a naval aircraft type in the mid-1930s, fighters were designed primarily as gun platforms. However, the strength and power that characterized the F4U and F6F enabled them to be readily modified to fighter/bombers. Each could carry forward-firing rockets, two 1,000 pound bombs or a droppable fuel tank. The proportion of fighters assigned to fast carriers increased steadily from 25 percent of complement in 1942 to 50 percent in 1944 to 70 percent in 1945. The dual role made this great increase in air-to-air combat power possible with little loss in air-to-surface capability.”

How about a Hellcat II, aka Tomcat II? The first order of business would be to resurrect as many retired F-14s (of any configuration) as we can. Second, combine these with fleet F-14As, the remaining F-14As and even the Iranian F-14 assets that might be obtainable (Iran took delivery of approximately 80 F-14s under the Shah; about 30 are still airworthy). Third, design a program to upgrade all of these aircraft for F-14Ds. This may sound wild, but Grumman experience in restoring Malaysian A4D basket cases to mind condition in the ‘80s was very successful, and they were not even Grumman airplanes! Similar success in restoring fleet A-6s at Grumman’s St. Augustine, Florida, facility was achieved. It would appropriate for the Navy or DoD to launch a study by a blue ribbon team under aegis of NAVAIR. We estimate that about 200 additional F-14s could be brought back into the fleet. The titanium box beams and bulkheads are nearly indestructible as well as reparable using electron-beam welding; but this is not yet a Tomcat II.

Buying time with these programs would allow the convening of a design team – again led by NAVAIR – of contractor personnel, MIT scientists and other university help to study the cost of building new F-14s. We think the following design changes to the F-14D are achievable for a new baseline airplane and later for block change improvements:

1. Increase high-value-weapon bring-back capability; this would mean that the F-14D, carrying heavy stores, would hit the arresting gear too fast. We could conclude that a bigger wing with more powerful high-lift flaps and slats is required, but fly-by-wire systems allow a more elegant solution.

2. With flaps down, the basic F-14 needs a down tail load to trim out the flap nose-down pitching moment. Allowing the aircraft to fly slightly unstable in pitch, now enabled by fly-by-wire technology, suggests the use of a canard, which would produce uploads and relieve the down tail loads.

3. The net result of these changes is that an increase of 4,500 pounds in bring-back store weight could be allowed; this is equivalent to a decrease in approach speed of 12 knots. The relief of down tail loads also solves an aft fuselage maneuvering fatigue problem and brings an air combat maneuvering lift increase by 19 percent. Turning (lift to drag) is also improved by relieving down tail loads. This change could be readily achieved because no primary structure is involved. A further plus of this design change would be that the aircraft’s internal fuel capacity could be increased by several thousand pounds.

4. We appreciate the value of staying with a variable-sweep design – especially for the podded, twin-engine F-14. First, we could have a carrier aircraft with landing speeds in the order of 130 knots versus the F-4 Phantom at 145 knots. At the other end, the mission payload/range is greatly increased by flying unswept, as is air combat maneuvering. Why the latter? Because dedicated air combat occurs at below about 0.8 because of high turning drag – an arena in which the F-14’s 20-degree sweep is optimal. And, of course, the F-14 has been to Mach 2.51 with four Sparrows loaded at 68 degrees of wing sweep. It has flown to Mach 1.35 at 5,000 feet (813 knots IAS), at which point the throttle had to be retarded to avoid over-speed.

5. [At this point, the article jumps to what should be #5 in this list. It continues…]…be redesigned to cope with the level of instability induced by the larger glove, which is minus fiver percent in clean flight and minus 13 percent flaps down at the most aft CG. This is no big deal and, in fact, it may be within the capability of the existing F-14D bobweight system that tolerates some longitudinal instability. For reference, the Grumman X-29 was 45 percent instable!

6. The F-14D should have some reasonable stealth-enhancing additions – “sensible stealth” as we used to call it – which would have practically no impact on weight or performance! A lot of work was done to this end in around 1990; it included full-scale tests on real F-14s. Some radar signature experts know exactly what should be done. Comparing the basic radar signatures, the F-14 has a slight fundamental disadvantage: it is larger. Its tunnel mounted attack stores make, however, virtually no contribution to its signature, and it does not carry a forest of wing tanks and weapons on long-range strike missions (this also keeps its signature down).

The baseline F-14D production aircraft defined above would allow these carefully considered modifications:

1. The installation of the F-119 or the F-120 engines. The F-119 has already been checked for fit. Upgrades of the GE F-110 might also be viable. The objective would be a 40,000-pound class turbofan.

2. The installation of two-axis, vectorable, axially symmetric engine nozzles for super augmented pitch, roll and yaw control.

3. The installation of UHF antennas that would be embedded in the increased-chord leading-edge slats to allow onboard detection and tracking of stealthy adversaries. Low-frequency radar works well against low-radar-cross-section objects. Arrays like this were tested at Grumman in around 1990.

In 1990, Grumman defined many versions of what it thought the F-14D could be. It was somewhat overdone in the stealth arena, but it incorporates most of the aforementioned ideas with very little design change or combat penalty. All the changes are cosmetic “tin” and not basic to the structure.

Just as commercial airlines are reaching their design limitations as fighter designs have matured, they, too, have encountered the limits imposed by the laws of physics. Fighters and airliners are in the same situation, but fighters include a couple of extra dimensions. For instance, a choice has to be made between supersonic flight and subsonic combat maneuvering and cruise efficiency. The same is true of stealth versus electronic warfare. Pick one and design toward it. If you want a V/STOL, design one, but don’t try to make it into a tri-service fighter/bomber.

If you want a long-lasting, long-range fighter/bomber, design it from scratch for the mission as a new or upgraded design – preferably the latter. Then equip it with modern weapons, sensors, surveillance, communications and EW. Let the sensors and computers – on board and remote – give the crew complete knowledge of the situation in the volume of air they are trying to dominate also, and suggest the best plays. The electronics will continue to advance rapidly to provide capabilities that are now only dimly perceived, but the basic airplane, regardless of who designs it, is quickly approaching the best that it can be. In the meantime, remember to give the crew IR missiles and a Gatlin gun for those times at which Murphy intervenes and high-tech warfare once again deteriorates to the usual groveling dogfight.

The bottom line is that, unless aircraft like the F-14D continue to be on board, U.S. Navy aircraft carriers on their flight decks, and most of those will be deployed with a few aircraft on their flight decks, and most of those will be versions of the Hornet and the Super Hornet. Despite all protests to the contrary, with regard to standoff munitions and precision guided weapons, our carrier battle forces will not have the pulverizing power of their 1980s counterparts. When that time arrives, it will be the beginning of the end for carrier forces as we know them today – and the end of their rapid availability to the President in times of need.

In 1975, an A-7 Corsair II was mounted on a pedestal outside the now closed Navy Master Jet Base, Cecil Field, Florida. On the base of the pedestal was a large bronze plaque bearing the inscription: “The main battery of the fleet.” The battle groups in those days – equipped with Corsair Iis and A-6 Intruders – could truly “kick ass and take names.” Those days may be over – probably forever – unless strong USN action is taken. We can learn major lessons from our past. Lets hope the Navy and the politicians remember to apply these lessons to the future. So Mr. President, ask not what your carriers can do for you, but what you can do for your carriers.

Wasn't the A/F-18 almost dropped during development because of its lack of legs? And isn't the F-18 a development of the F-17 from the mid-70's? It's impossible to kill these lousy aircraft programs. Don't start me on the Osprey.

And not only that--but I think F-18's are pretty homely, especially compared to an F-14.

Walt

There used to a plastic kit of the A7 marketed that called it "The fist of the fleet."

But wasn't the A7 a disappointment also?

Walt

And not only that--but I think F-18's are pretty homely, especially compared to an F-14.

Northrup developed the F/17 in the 1970's. It was the prototype for the F/18. The original is in an naval air museum (or was in the mid 1980s). That was in Pensacola, Florida.

There can be a lot of politics around military procurement.

This whole piece ignores the (extremely substantial) costs of RDT&Eing a new Tomcat, and it wouldn't enter the fleet until 2012 at the earliest.

Once again, NAVAIR partisans push for an airplane that the budget will not support. Didn't we learn our lesson with the A-12?

the author spends a lot of good time defending his point, which is well made. He speaks of the area AND radius of influence. (dropping by 23%) What he doesn't appear to talk about as well is the loss of the Phoenix AAM along with the Tomcat. The "Slammer" is a fine missile, but it doesn't have the range or punch of a Phoenix. Also, I understand a modern vectored thrust aircraft can defeat any Slammer the pilot sees in time. Not so with the Phoenix.

Emotionally, I love the Tomcat, and it is definitely the 'baddest' looking aircraft when viewed nose on and loaded out. If the Buf can fly for 50 years, fo can the Tomcat.

The Navy should have never let the A-6 go. That was the best medium attack all weather aircraft ever produced.

The Navy had a choice between procuring the A-6F, and RDT&Eing the A-12. They chose the latter, and drove it straight into the ground.

Also, when the A-12 contractual default judgement is finally charged to the Navy, it will wipe out the entire year's Naval Aviation funding line and then some.

Can't argue with the financials, but can the bean counters justify downgrading EVERY CAG in the fleet? What's the justification for that?

Unless of course the Super Hornet can be made truly Super.

Also, I understand a modern vectored thrust aircraft can defeat any Slammer the pilot sees in time. Not so with the Phoenix.

Two points: first, the Slammer is MUCH harder to see than the Phoenix is. Second, if the pilot is good enough to beat the Slammer, he WILL beat the Phoenix: it's not a dogfight missile, it was designed to splash large bombers. It's not especially maneuverable.

We get the aircraft we can afford. Or we get no aircraft. Those are your choices. Congress is unwilling to fund anything as expensive as the Super-Duper Tomcat would be.

The Navy needs to build a Common Support Aircraft to replace the C-2, E-2, and S-3. If they do not, then the aircraft carrier is going to become irrelevant--because it will become just another set of TACAIR strike/fighter birds, just like the Air Force, only more expensive. NAVAIR needs to develop unique capabilities that nobody else does--or NAVAIR is going to disappear.

Northrup developed the F/17 in the 1970's. It was the prototype for the F/18.

Truth be known, the YF-17 lost a competitive flyoff to the F-16 as the lightweight fighter compliment to the F-15. The Air Force rated it second best 30 years ago

We get the aircraft we can afford. Or we get no aircraft. Those are your choices. Congress is unwilling to fund anything as expensive as the Super-Duper Tomcat would be.

Would that be the $100M F-22 or the $60M JSF?

I agree-- just depends upon what mission the flight is sent up for. If the mission is fleet defense, the Super Hornet just won't cut it when it comes to flying CAP. "Fighters" seeking ACM aren't a direct threat to the fleet. It's the missile carrying 'bombers' that are, and we want them splashed before they get in range. The Phoenix was designed for just that mission, and while the SOVIET threat is gone, the ALCM threat is as real as ever in Asia. An F-14D carrying Phoenix, AND AIM-7s AND AIM-9s AND 20MM is a better fleet defense and CAP platform than the F-18X. Why kill it except for finances? (BTW, I honestly don't buy the argument about the F-18 being insufficient for air-mud).

Question for you -- the flight profile of a Phoenix, as I understand it, is to fly very high above an approaching aircraft and plummet down on it at very high speed and frag with a wide lethality cone, whereas the Slammer is more hunt-you-and-kill-you, and can be physically evaded and defeated. Why do you think the Phoenix in actual use is easier (for a missile carrying platform)to evade?

Isn't the newly awarded Lockheed JSF scheduled to replace both the F14 and F18? If so, why not a comparison of the JSF's capabilities vs. the F14. Perhaps the JSF is too early in development to make any reasonable comparisons. Thoughts anyone?

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