“Senator, there isn’t enough power in all of Christendom to make that airplane what we want” VADM Tom Connolly testifying before the Senate Armed Services Committee (1968)
In Part I we explored some of the politics (and politicking) behind the TFX – the program to provide the Air Force and Navy with a common next generation fighter. For the Air Force it was to be a long-range fighter-bomber with tree-top level supersonic dash capabilities. For Navy, it was the Fleet Air Defense mission, armed with long-range missiles. After several proposals were forwarded by Boeing and General Dynamics that fell short of Service requirements, a final selection was made in November 1962 in favor of GD despite the two Services preference for the Boeing proposal. For the next six years, the design, especially the Navy design, would be dogged by political bickering and infighting between Navy and OSD. But what was the aircraft itself like? Was it really that bad?
GD and Boeing came to the table early in the process with impressive pedigrees as aircraft manufacturers on the cutting edge of technology. Boeing for having brought not one, but two all jet bombers into service for the Air Force, fielded with a new jet tanker (which formed the basis for the highly successful 707 commercial jet) and was in the process of building the next generation of ICBM, the Minuteman. GD, through its Convair division, had developed and produced the F-102 and F-106 delta-winged fighters, the latter of which was equipped to participate in the computerized Semi-Automatic Ground Environment (SAGE), an automated control system used by NORAD for collecting, tracking and intercepting enemy bomber that could automatically direct aircraft to an interception by sending commands directly to the aircraft’s autopilot. It raised the bar in aircraft materials with the revolutionary B-58 which was just reaching the end of manufacture.
Boeing TFX Proposal GD TFX proposal
Boeing’s solution was essentially two different aircraft that shared some common elements like the wing-box, engines, aircraft control and power systems and escape system. GD, partnered with Grumman, would provide an aircraft that was a common airframe, modified slightly for the Service specific mission. Hence the navy variant would have longer wings to help provide greater endurance, a shorter nose to permit better visibility in the CV-landing pattern and smaller footprint (or “multiple”) on the flight deck. A signature feature was the weapons system, the Hughes AN/ASG-18/AIM-47 Super Falcon, a 100nm air-intercept missile developed from the GAR-9. Already tested in the YF-12 (six of seven intercept attempts were successful), it eventually formed the basis of the AN/AWG-9/AIM-54 Phoenix, two of which were to be carried internally on the Navy’s F-111B and four on swiveling wing pylons. Power would be provided by a naval version of the Pratt & Whitney TF30. The F-111B would be entirely built by Grumman while Grumman would also provide the rear fuselage, under-carriage and stabilizers for the Air Force’s F-111 (and later FB-111).
BuNo 151970, the first F-111B flew from Grumman’s facilities at Calverton on 18 May 1965 and ran into the same problems experienced by the F-111A, namely inlet-induced compressor stalls in various parts of the flight envelope. Notwithstanding that issue, initial flight trials went fairly well with the first Naval Preliminary Evaluation held at NAS Pax River in October 1965. By this point the problem that would eventually be the downfall of the F-111B was becoming apparent – weight.
All through the requirements process there had been back-and-forth arguments between Navy and Air Force and Navy and OSD over the aircraft upper weight limit. At some points the Navy actually abstained from the joint requirements process, but an eventual upper limit of 55,000 lbs fully loaded was set. For reference, comparable aircraft weights at the time were:
- KA-3: 70,000 lb loaded (82,000 lb max takeoff wt)
- A-5A: 47,530 lb loaded (62,950 lb max takeoff wt)
- F-4B: 41,500 lb loaded (62,000 lb max takeoff wt)
- E-2A: 51,600 lb loaded (55,500 lb max takeoff wt)
Even before first flight, the F-111B was conservatively estimated to weigh in at nearly 78,000 lb (exceeding the F-14’s 74,350 lb max take off weight). With this in mind GD-Grumman embarked on a series of weight savings programs, starting with the Super Weight Improvement Program, or SWIP, which consisted of mainly internal changes and wrapped up with the Colossal Weight Improvement Program, CWIP, which brought external changes as well. Still, the death spiral was on. By the time a Navy-funded Anti-Air Warfare study was completed in 1967, fuel requirements for the F-111B to meet its original mission had climbed from 16,000 to 26,000 lbs, challenging the already short on thrust TF-30-P-1 engines. To rectify this situation, the engines were upgraded to the 12,290 lb dry thrust rated TF-30-P-12 engines.
Unsatisfactory in the FAD role due to complexity and limited range, the F-111B also fell short of the mark for air superiority due to weight and maneuvering ability compared to the F-4 Phantom which it would be replacing. Experience from Vietnam was beginning to feed in to the program as well where it was becoming apparent that assumptions made at the end of the last decade about air warfare were being overturned (and would lead to the now famous Ault Report and creation of the Navy Fighter Weapons School, better known as Top Gun). The F-111B was a slug, requiring over 6 minutes to accelerate from .8 to 1.8 Mach at 35,000 ft – by comparison the F-4, the fighter the F-111B was to replace, took less than half the amount of time. Turn rates were similarly poor.
The Navy was increasingly growing unhappy and was vocal about it. The weight issue was so great that McNamara started holding bi-weekly Saturday AM meetings on “the F-111B problem” in an attempt to spur the principals to find a solution. They didn’t. In an interview conducted in 2003 on Defense Acquisition, Paul Ignatius, who was SECNAV in 1967-68, was asked about the F-111B and the climate at the time:
INTERVIEWER: I can’t resist asking a question about the F-111 and what happened to it. Now I assume when you came in ’67 you must have walked into a brick wall of resistance in the Navy.
MR. IGNATIUS: You are quite right. I came into the Department of Defense in 1961 and had nothing to do with the F-111 until 1967, when I became Secretary of the Navy, and I did run into a brick wall. The Navy was dead set against the airplane. It was highly emotional.
Here was a case where McNamara, I think, expected me to keep the admirals in line. The more I looked into it, the more I became convinced that the matter had reached such an emotional state that even if the F-111B, the Navy version, turned out to be an excellent airplane, and it wasn’t all that good, but even if it did, the Navy still wouldn’t want it.
So I went to McNamara and said, “You may not like it, but it seems to me we have got to face reality here. Congress is turning against this. The Navy doesn’t want it.” When I say “the Navy” I am talking about the aviators in the Navy.
I said, “I have talked with ADM Moorer about this and he and I have agreed that what we need to do is undertake a study of just what kind of airplane the Navy needs.” And I said, “I’ll tell you one thing if we do go down this route and we procure a new aircraft we are going to do it competitively.”
Bob wasn’t happy, but I think he had other things to concern him and maybe he was persuaded that it was an inevitable conclusion. We stayed in the program but meanwhile a successor airplane was studied. If I remember right we asked Bud Zumwalt to do the study. He was a black shoe naval officer and not an aviator, and that was an advantage in his case.
Then a so-called unsolicited and I use that term deliberately, “so-called unsolicited” bid– came in from Grumman for a successor airplane. When we had made a decision to go to a new airplane, I insisted that it be done under competitive procedures. We had a lively competition with two excellent airplanes proposed, one by McDonnell Douglas and the other by Grumman, the so-called unsolicited proposal that Grumman had submitted.
As it turned out, the Navy selected the Grumman airplane. It became the F-14 Tomcat, and the McDonnell airplane became the F-15 that the Air Force bought. The F-111 was born in controversy. The Navy version died in controversy. It was a problem with the Congress at the outset when McNamara and Zuckert had to defend their selection of General Dynamics over Boeing for the airplane and it was a controversy when I was the Navy Secretary and had to go and testify before Senator Stennis with Tom Moorer and the Navy’s top aviator, VADM Connolly, with me.
It finally all worked out, but it was a contentious and difficult matter. I am not sure I know what the lessons are that one learns from this. It is true that demands on a Navy airplane are different because of shipboard operations from those on the Air Force. On the other hand, the idea of commonality when you can achieve it makes awfully good sense. People forget that the F-4 had both a Navy and an Air Force version, and it worked well in both services. The tensions that grew up around the F-111 became so great and so emotional that you just had to scissor it off and let the Navy have its own way.
Following VADM Connolly’s testimony and another Navy-funded study in 1968, the F-111B was dead. The program was terminated save for the few prototypes on hand which were flown until 1971 in a data collection-mode that included CQ on USS Coral Sea (CVA 43). Two of the prototypes crashed – one off Long Island in July 1967 and another off the southern California coast in Sept 1968.
All was not lost though as a replacement was warming up off stage via the VFX-1 study…