Storms of Controversy. Palmiro Campagna
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would eventually be issued as RCAF specification Air-7-4.
More information was requested on the aerodynamic claims, and it soon became clear that aerodynamic data had to be confirmed by wind-tunnel testing. Avro conducted the tests between August 27 and September 2, 1953, at the Cornell Transonic Wind Tunnel in Buffalo, New York. The resulting reports were sent to the NAE on September 18 for comment. In his September 28 reply to then Air Vice Marshal Douglas M. Smith (air member technical services), John H. Parkin, director of the NAE, stated, “[T]he Cornell wind-tunnel tests indicate that, aerodynamically, the C105/1200 configuration is capable of meeting its performance requirements, although it is important that wind-tunnel measurements be extended to higher Mach numbers as soon as possible.” Parkin was stating that while results were good, they were somewhat limited in terms of the speeds tested and needed to be extended in order to evaluate the aircraft’s performance at higher velocities it was expected to achieve.14
Smith’s position as air member technical services made him directly responsible for the aircraft program. He reported directly to the chief of the air staff, who in turn reported directly or through the chairman of chiefs of staff to the Cabinet ministers. Hence, Air Vice Marshal Smith reported to Air Marshal C. Roy Slemon, chief of the air staff. Air Vice Marshal Max M. Hendrick would replace Smith as air member technical services in 1955, and Slemon would be replaced by Air Marshal Hugh Campbell in 1957. It would not be until 1957 that a separate project office dealing exclusively with the Arrow project would be created under the chief of aeronautical engineering, Air Commodore Gordon G. Truscott, who would report directly to the air member technical services. Truscott had been a pre-war officer, graduate engineer, and pilot who supported the Arrow project.
As work at the Avro plant continued, the RCAF conducted an investigation to determine if any foreign aircraft could satisfy the requirements. In his submission to the Cabinet Defence Committee on November 30, 1953, Liberal Minister of National Defence the Honourable Brooke Claxton stated the following:
With the object of economy and to avoid unnecessary duplication, every effort has been made to determine whether future U.K. or U.S. aircraft could meet our requirements. In the U.K. the only aircraft for consideration is the Javelin whose performance falls far short of the requirement. In the United States there is the Convair F-102 which is a single-engine, single-seat aircraft designed to carry a fully automatic armament which is now under development. This aircraft does not meet the range requirement set out and its manoeuvrability and ceiling are below our studied requirements. In addition, this aircraft is so highly specialized that if the planned development of any major element breaks down there is little flexibility in the design to permit substitution of alternate equipment. Further, this aircraft because of its design and layout does not have much development potential and is, therefore, liable to become obsolescent in a relatively short time. Adoption by Canada of this aircraft involves calculated risks greater than we are justified in taking. The RCAF, therefore have had A.V. Roe Canada work out an engineering proposal for an aircraft to meet our specification.15
The minister went on to outline that the Treasury Board had authorized an expenditure of $200,000 on May 8, 1953, and an additional $300,000 on July 21. These monies had been spent on design studies and wind-tunnel testing. He stressed that if the program were begun in earnest, a prototype could be completed by October 1956, with production by 1959. He then sought approval for the development to commence. Expenditures would be $26,925,000 spread over a period extending into 1958 and would include some $4 million in government-supplied equipment. Engines would be the most suitable ones found in either the United States or Britain. Two prototype aircraft would be built. Claxton was successful, and Avro was awarded a design-and-development contract in March 1954; the CF-105 design began in May of that year.
The RCAF specifications, which no foreign aircraft could meet, included a supersonic combat radius of 200 nautical miles, a combat ceiling of not less than 60,000 feet, a maximum speed at altitude of Mach 2, a rate of climb not more than six minutes to 50,000 feet, twin engines, a crew capacity of two, an all-weather capability, and a manoeuvrability of 2 g at Mach 1.5 at 50,000 feet without loss of speed or altitude. Also, the aircraft had to provide as much flexibility as possible for engines and armament capacity due to the uncertain availability of those under consideration. In the words of Claxton, the requirements had been developed by the RCAF “in conjunction with the DRB, the NAE, the United States Air Force, Department of Defence Production and various aircraft manufacturers both in the United States and the United Kingdom.”16 He had every confidence that Avro would be equal to the task.
Although the NAE had initially agreed that the C-105 configuration would meet its required performance, Air Vice Marshal Smith received another letter from Parkin dated January 15, 1954. This time the NAE director noted that his comments of September had been premature. The full assessment of Avro’s work was now complete and available in NAE report No. LR-87, “Assessment of the Performance Characteristics of the Proposed A.V. Roe C105/1200 All-Weather Supersonic Fighter Aircraft.” Essentially, the report concluded that the aircraft would not meet the required 200-nautical-mile radius nor the 2-g manoeuvrability because the supersonic drag (air resistance) was far greater than Avro’s estimate. Smith, however, countered that even if drag were increased, the aircraft would meet the combat radius due to the increased fuel capacity Avro had included. He states as much in a memo to the chief of the air staff, Air Marshal Slemon, on February 16, 1954. On the question of whether the amount of drag calculated by Avro was correct, Smith noted that wind-tunnel testing to verify the numbers was ongoing. This would prove to be the beginning of a long series of disagreements between the NAE and Avro that would carry through over the length of the project.17
Despite assurances, the uncertainties about the aircraft’s performance persisted, and the disagreements between the NAE and Avro increased. In an internal NAE memo dated September 29, 1953, the following is noted: “[O]ur opinions differ in various ways from those of the Company or the RCAF, and this has given rise to argument and possibly to some ill feeling, even to the opinion that the NAE is anxious to hinder the straightforward development of the aircraft. Nothing could be further from the truth.”18
While the NAE saw itself as a legitimate scientific watchdog over a very complex project, its tone may have suggested otherwise; more than one official at Avro and the RCAF recalls that the NAE may have taken the role of honest broker just one step too far. The RCAF finally requested a meeting between the NAE, the DRB, and the U.S. National Advisory Committee for Aeronautics (NACA, later NASA) to discuss the differences between the NAE estimates of performance and those of Avro. At the time, it was believed that the best aeronautical minds were at NACA. The group published the “Joint Report on an RCAF-DRB-NAE Visit to NACA Langley Laboratories to Discuss Aerodynamic Problems of Avro CF-105 Aircraft,” dated November 19, 1954.
The NAE had made its points, for on December 20 and 21, 1954, Avro was called to the carpet. A second meeting was held at NACA headquarters in Washington, with Avro engineers taking centre stage to explain the reasoning behind their more favourable performance figures. Jim Floyd and Jim Chamberlin were among those present from Avro. Items discussed included the NAE criticisms of drag calculations, use of wing negative camber rather than positive camber, and perceived problems with pitch-up, engine intakes, and overall stability.
On the crucial issue of drag, NACA backed Avro, stating, “It was basically agreed … provided that (a) the intake and ramp bleed area is investigated and cleaned up where necessary, and (b) the afterbody is well faired in after the nozzles, the zero lift drag at Mach 1.5 may be as low as .020…. The Avro estimate from area distribution and skin friction considerations was .0184. The configuration is considered to be generally reasonable with respect to drag.”
Avro had proposed the use of negative wing camber rather than the traditional positive camber, which caused the NAE some consternation. Again, NACA concluded in favour of Avro: “It was agreed that there is little to be gained by conical positive camber for the particular mission of this aircraft…. Avro’s reasons for going to negative camber were also understood and appeared reasonable.”
The NAE thought the aircraft would be susceptible to pitch-up in supersonic flight. NACA stated, “It was agreed that the notch or leading edge extension proposed by Avro should alleviate pitch-up.”