The XVII was very similar to the XV except that the engine was modified to give extra power for take-off. The sting tail hook and teardrop hood were made standard. The preferred armament was now four 20mm cannon. Some were completed as reconnaissance aircraft, in which guise they were called FR MK17. Late XVII models featured a long-stroke undercarriage which greatly assisted carrier landings and an increased range due to a fuel tank behind the pilot and “plumbing” for wing mounted “slipper” fuel tanks. 232 produced.