Durandals: The Formidable Penetrators of PAF

The Durandal is a anti-runway penetration bomb developed by the then Matra of France, which is now known as the MBDA,  designed to destroy airport and airfield runways.

The Durandal was adopted by the US in a slightly modified form (with a steeper impact angle and a higher 630 knot deployment speed) as the BLU-107/B in the 1980s, and carried by F-111 and F-15E strike aircraft.

This Durandal is in service with Argentina, Turkey, Pakistan and at least 13 other nations. There is some obscure information as to whether the Durandal is or ever has been in service with the French Armée de l'Air.

In the war it was used by the USAF in Desert Storm. 20th Wing (operating F-111E's) flight commander Captain George Kelman said "there is nothing better at destroying a runway than a Durandal."

China has developed its own anti-runway bombs, the Type 200A, based on Durandals.
Durandals are Designed to be dropped from low altitudes, the bomb's fall is slowed by a parachute. 

• The maximum release speed is 550 knots (1,020 km/h; 630 mph), and 
• The minimum release altitude is 200 feet (61 m). 

When the bomb has reached a 40° angle due to the parachute's drag, it fires a rocket booster that accelerates it into the runway surface. 

It works in a way of "dual action":

1. The 100-kilogram (220 lb) primary charge explodes after the penetration of the weapon into the concrete and drives the secondary charge even deeper.
2. The 15-kilogram (33 lb) secondary charge then explodes after a one-second delay.  
   

Later production weapons have a programmable fuze that can delay the secondary detonation up to several hours. The weapon can penetrate up to 40 centimetres (16 in) of concrete, and creates a crater 2 metres (6 ft 7 in) deep and approximately 5 metres (16 ft) in diameter. In addition, concrete slabs around the crater are disturbed in an area approximately 15 metres (49 ft) in diameter. The disturbed slabs are displaced up to 50 centimetres (20 in) above the original surface, making repair more difficult than the simple crater from a conventional bomb