Jan Zurakowski:
Test Flying the Arrow. pg4

continued from page 3,

I realized during my landing run that the undercarriage was retracting. Since my speed was too low to get airborne again, I switched off the engines and the aircraft skidded to a stop, damaging the flaps badly. After an investigation had been carried out in the hangar, it was determined that everything was in perfect order; lowering and raising of the undercarriage functioned properly and the indicators were correct. Conclusion: pilot error.

     I was called to the hangar to see for myself. I set all the controls and switches as I had during landing, operated the undercarriage several times, and, sure enough, every­thing was just fine. I was just getting out of the cockpit when the foreman said: "You see, that's a really good old aircraft", and enthusiastically slapped the fuselage with his hand. That started it. All by itself, the undercarriage retracted.

     It was later established that somehow the wiring of the master auto-observer switch was mixed up with the under­carriage selector wiring and that a short caused by the vibration of the aircraft as it touched down caused the undercarriage to retract. "Too many gremlins." That was how a case like this would generally be described in England.

     In the meantime, production of the CF-100 and the Orenda engine was going on at a good pace. The aircraft had a good name in Canada and abroad, and the Avro company decided to demonstrate it at the Farnborough show in England, organized every second year by the Society of British Aircraft Constructors.

     I demonstrated the CF-100 Mk. IV at Farnborough in 1955, and we made an attempt to sell the aircraft in Holland and Belgium. The Dutch Air Force had a rather poor fighter aircraft from the U. S. and needed a replacement, but they didn't want to upset their American friends. The Belgian Air Force had had bad experience with American aircraft, so they purchased the Hawker Hunter from England. The Hunter was in its early development and the cost of essential modifications in the first year was higher than the cost of the original aircraft.

     In night fighter class the Meteor NF 14 in the Royal Air Force was inferior to the CF-100 in range, speed and armament, and the Gloster company was still solving low­speed instability of the Javelin by redesigning the wings, but loss of two pilots and a few aircraft was delaying development. We were in a favourable position, and a contract for sale of fifty-three CF-100 Mk. V's was signed with Belgium.

     In the Canadian Aviation magazine dated March 1975, I noticed the statement that sales to other countries were restricted for security reasons because the CF-100 was equipped with the Hughes radar produced in the United States.

    A small comparison: Between the first flight of the Javelin and the first Javelin in a squadron, there elapsed over six years. The CF-100 Mk. II took less than two years. For the Mk. IV it was less than four years.

     Looking back 25 years, I think that the CF-100 was a very good and reliable aircraft, which at the time satisfied the operational requirement of the Air Force. Taking into account that it was the first military aircraft designed and built in Canada by a very young company, I think it should be considered a great success.

     In August 1955 the U. S. Air Force announced a contract with Avro Aircraft to explore "a new design concept" - later known as a flying saucer. "Spud" Potocki was the development pilot of this project, whilst I was concentrating on the development of the Arrow.

     The idea of a supersonic interceptor, known later as the Arrow, started in 1951 when the
A. V. Roe team under Jim Floyd submitted a brochure to the RCAF containing three proposals for supersonic fighters. I would like to mention here that for the first time a Canadian, Jim Floyd, was awarded the Wright Brothers Medal for outstanding achievement in aeronautical science. All previous winners had been Americans.

     In March 1952 an operational requirement was received from the RCAF for an all-weather interceptor. In June 1952 the company presented two proposals: a single- and twin-engine delta-wing interceptors with crews of two.

 

In June 1953, after long consultations with the Air Force and the National Aeronautical Establishment, the company presented the CF-105 proposal and obtained instructions to go ahead with design study.

     A series of wind tunnel tests followed at NAE (Ottawa), Cornell Aeronautical Laboratories (Buffalo) and NACA (Cleveland and Langley Field). Simulation of free flight at supersonic speeds was carried out by rocket-propelled models.

     Later in 1954 changes in the proposed powerplant were made. Because Rolls-Royce RP-106 development was delayed and the Curtiss-Wright J-67 was expected to be too late as well, the installation of a Pratt & Whitney
J-75 as an interim measure was accepted with the Orenda Iroquois engine intended for production models.

     As design investigation progressed it became apparent that there were new problems connected with the increase in speed from Mach 0.87 of the CF-100 to the more than Mach 2 of the new interceptor. This increase of more than 750 MPH called for a lot of electronic systems needed for successful interception, automatic flight, weapon fire controls and navigational systems. I would like to point out that during the five years of the war, a time of most intensive development, the speed of RAF fighters increased by only about 100 MPH.

     We in the Flight Test Section hoped that we would be part of the team, and participate in the solution of problems which we would have to face sooner or later. There was a rumour that the directional stability of our new aircraft was poor, and at this time a number of American fighters disintegrated in the air and some designs were quickly modified to provide a bigger fin area.

     We asked the design office for aerodynamic reports. We met with refusal because "there could be a wrong interpretation of the reports by the pilots". I asked my Chief Test Pilot, Don Rogers, for help, but when his efforts were stalled, I tendered my resignation as the Chief Development Pilot. This title created an impression that I am to some extent responsible for development - but how could I be, if I was kept in the dark?

     It came to the attention of Jim Floyd, Vice President of Engineering, that the latest estimates of landing speed of the Arrow were much higher than the initial one, so a meeting of aerodynamic experts was called and I was invited. After a short discussion he asked me what I thought about it. My answer was that I did not know, because my request for reports had been refused. It was a bit of a shock to him, because he had previously instructed that reports be made available to the flight test section. After this, one of the aerodynamicists refused once again to supply reports. He was promptly fired, and the next morning all required reports were in the flight test section. Yes, there was a problem with aircraft directional stability under some flight conditions.

     Which solution was right? First, to increase stability by aerodynamic changes which would involve a weight penalty without any guarantee that all the flight conditions would be satisfactory. Or second, introduce reliable electronic stability augmentation needed anyway for the weapons system.

     The latter choice was made, but it involved the risk of developing and proving the system on an aircraft otherwise unsafe under some conditions if the system failed. Loss of an aircraft in early development could be a disaster for the company.

     Cooperation of other sections with the flight test section was good. Freshly introduced human factors engineers helped in finalizing the cockpit layout. The number of instruments, switches, etc. was reduced in the Arrow to 70% of that in the CF-100, and a master warning light was introduced, with a panel indicating the trouble.

     A Royal Canadian Air Force detachment was established at the Company under S/L Ken Owen, with F/L Jack Woodman, a highly experienced test pilot. This detachment was most useful in an advisory and cross-checking capacity. The problem we had with wheel brakes can best illustrate the need for a cross-checking system.