The Civil Aviation Authority of the Philippines ordered the grounding Wednesday of all helicopters produced by the Robinson Helicopter Company following the recent incident where Quezon Governor Rafael Nantes along with four other people were killed following the helicopter crash last Monday.

CAAP Director General Alfonso Cusi issued a memorandum Wednesday grounding all 51 Robinson R-44 helicopters in the country as the investigation on the crash is still ongoing.

According to Cusi, all but 50 of the Robinson R-44 helicopters in the country are privately owned--with the Philippine government also owning one.

Cusi described the Robinson R-44 is a light utility helicopter that can carry four passengers, including the pilot. The aircraft is a single-engine chopper with a semi-rigid two-bladed main rotor. It has an enclosed cabin with two rows of side-by-side seating for a pilot and three passengers.

The helicopter was designed by Frank Robinson in the 1980s and was certified to fly by the US Federal Aviation Administration in December 1992. It has a range of 348 nautical miles.

Cusi added that all the R-44 choppers will remain grounded until the cause of the crash is determined and the airworthiness of all Robinson helicopters are assured.