Grrr-umman Wildcat
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[June 2013] |
In Shuttleworth’s hangar sits a Grumman Wildcat. It will have to wait patiently until the Spitfire’s long re-build is completed then it can be made ready for display, probably painted as a Royal Navy Martlet.
This tale will give you a flavour of its character.
The Wildcat was re-equipping the US Navy as its principal monoplane fighter when the Japanese attacked Pearl Harbor in 1941. After early encounters with the Mitsubishi Zero the Navy realised the Wildcat’s shortcomings. Although they urgently needed its more advanced replacement, the Hellcat, their immediate need was for more and more fighters so the production of the Wildcat couldn’t be delayed by major development and modification. The Navy wanted them NOW – faults and all. However, it was possible to upgrade the engine and a 1350 hp Wright was fitted. Carl Abner, newly appointed as a production test pilot, was briefed to carry out a terminal velocity dive with an 8G pullout.
He had never done such a dive before. The standard g-meter on the instrument panel would tell him what was going on and a Navy V-G recorder was fitted behind the cockpit to keep a record of the G and airspeed. Carl climbed to 25,000 ft, rolled it over and pulled into a vertical full-throttle dive. At 8000 ft he started the pull out, carefully watching the g-meter. These were the days before G-suits and he blacked out briefly at 7G but, when his vision returned, he found the meter reading only 7.2G. So he climbed back to 25,000’ and repeated the dive. A more vigorous pullout produced the same result, 7.2.
On his third attempt he decided to pull out as hard as he could. His blackout period last more than 30 seconds and the Wildcat was seen rolling and pitching all over the sky. 7.2 yet again. Carl realised that there was something about TV dives he didn’t understand so he landed to discuss it all with the Chief Test Pilot.
When the Wildcat was parked the crew tried to fold the wings but it was impossible. The wing panels were deformed to the extent that some rivets in the main spar had popped. The recording G-meter was checked and showed that Carl had pulled 9.5G, 11.5G and 12.5G. Then the cockpit G-meter was suspect. An assembly fault was found in it which prevented the needle moving past 7.2.
Grumman had a reputation for building strong aeroplanes. They were, after all, intended to be thrown brutally on to the decks of heaving carriers. The Wildcat’s design catered for an ultimate breaking load of 12G. So Carl was lucky and the Navy was quite satisfied with the results of the test. Grumman simply changed the wing panels and the engine mount and the Wildcat was duly delivered for service. The wing panels were repaired and fitted to another fuselage and that, too, entered service.
All this goes to justify the usual name for Grumman’s factory – the Ironworks.
He had never done such a dive before. The standard g-meter on the instrument panel would tell him what was going on and a Navy V-G recorder was fitted behind the cockpit to keep a record of the G and airspeed. Carl climbed to 25,000 ft, rolled it over and pulled into a vertical full-throttle dive. At 8000 ft he started the pull out, carefully watching the g-meter. These were the days before G-suits and he blacked out briefly at 7G but, when his vision returned, he found the meter reading only 7.2G. So he climbed back to 25,000’ and repeated the dive. A more vigorous pullout produced the same result, 7.2.
On his third attempt he decided to pull out as hard as he could. His blackout period last more than 30 seconds and the Wildcat was seen rolling and pitching all over the sky. 7.2 yet again. Carl realised that there was something about TV dives he didn’t understand so he landed to discuss it all with the Chief Test Pilot.
When the Wildcat was parked the crew tried to fold the wings but it was impossible. The wing panels were deformed to the extent that some rivets in the main spar had popped. The recording G-meter was checked and showed that Carl had pulled 9.5G, 11.5G and 12.5G. Then the cockpit G-meter was suspect. An assembly fault was found in it which prevented the needle moving past 7.2.
Grumman had a reputation for building strong aeroplanes. They were, after all, intended to be thrown brutally on to the decks of heaving carriers. The Wildcat’s design catered for an ultimate breaking load of 12G. So Carl was lucky and the Navy was quite satisfied with the results of the test. Grumman simply changed the wing panels and the engine mount and the Wildcat was duly delivered for service. The wing panels were repaired and fitted to another fuselage and that, too, entered service.
All this goes to justify the usual name for Grumman’s factory – the Ironworks.