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Home | Update | Latest Issue | Gallery | FR Profile | Datafiles | FR 2/97 HORNETS FOR SWITZERLAND by Peter Gunti Switzerland's decision for the McDonnell Douglas F/A-18 Hornet had not come easily: Even a referendum was to be carried out until the contracts could finally be signed at the end of June 1993. Since then "everything has been going according to schedule", says project manager Peter Lyoth from the Group Armament. The first two of the 34 aircraft ordered were assembled at the McDonnell Douglas plant in St. Louis, taking off for their first flights in January and April respectively. The first Swiss built Hornet was assembled at the "Schweizer Unternehmung für Flugzeuge und Systeme" (SF) in Emmen and accomplished its first flight on October 3. The two "American" Hornets were used for an extensive flight test program by the US Navy to verify the entire weapons system. Some of these tests, such as supersonic flights at low altitudes and life missile shots, can not be done in Switzerland, out of consideration for the people. While the avionics suite was tested in China Lake, California, the structural tests were done at the Navy flight test center in Patuxent River, Maryland. The major part of the verifications is related to the new weapons pylon (low drag pylon) which was developed by SF in Switzerland. Since most Hornet operators use the fighter in a multi-role concept, the American pylons are able to carry a variety of loads. However, the disadvantage is that these SUU-63 pylons are relatively heavy and generate a high drag. Also, the aircraft's angle of attack must be limited as soon as these pylons are mounted to the wingtips. Since the Swiss intend to use the F/A-18 solely in the air defence role, they recognized already in an early stage that a significant performance improvement is possible in this area. The necessary tests of the new pylons comprised of four phases. First, the flutter tests of the wings had to be repeated. A load program was used to measure the forces at the wings and the pylons during extreme maneuvers, comparing the measurements with the calculated data. Performance flights generated exact data of the aircraft's performance spectrum. Finally, the effects of releasing AIM-9P/5 Sidewinder and AIM-120B AMRAAM missiles were evaluated during separation tests. The test team comprised of a small group of Swiss specialists under the lead of test pilot Res Schmid and US Navy personnel. Still, the main party of the team were employees from McDonnell Douglas. The US manufacturer is very interested in the program since the performance improvements are not limited to new export customers. Several long-time operators of the F/A-18, such as Canada, Australia or Spain can increase the capabilities of their Hornets through the update. McDonnell Douglas test pilots were particularly responsible for the envelope expansions since, according to a Navy regulation, these have to be granted by the aircraft manufacturer. The fact that the flight tests of the F/A-18E/F prototypes were done at the same time in Patuxent River was advantagous for the Swiss program. On most flights, a KC-130 tanker could be shared with the colleagues from the other hangar, making the test flights highly efficient. The F/A-18 test program is very important to the Group Armament of the Swiss Military Department, which is accustomed to a high degree of independence due to the Swiss neutrality. Even though thorough data existed already at other places, the experiences from the tests ensure that the country can take the engineering responsibility for the product, which will stay in service for several decades. Switzerland particularly demanded a higher service time for its aircraft. Due to this fact, Northrop Grumman, which is responsible for the aft fuselage structure, builds the main spars out of a stronger titan alloy, extending the lifespan from 3000 to 5000 flight hours. The first two aircraft have been fitted with a test instrumentation to gather data about the effects of the new spars on the rest of the structure. Other than the described alterations, Switzerland was reserved on changing the aircraft, such limiting the extra costs. Up until this point, the Sfr 3,495 billion program is progressing well. The strong Swiss currency has even eased the budget somewhat, so that the earmarked reserves have yet gone untouched. From page 42 of FLUG REVUE 2/97 Home | Update | Latest Issue | Gallery | FR Profile | Datafiles | FR 2/97 Copyright 1997 by Motor-Presse Stuttgart. All rights reserved. Last updated January 10, 1997