ISLAMABAD - Pakistan is in the final stages of exercising an option to buy 18 more F-16 Block 52+ fighters, which would double its fleet of the Fighting Falcon's advanced variant, said Haris Khan of the Pakistan Military Consortium think tank. Deliveries of the 18 "Peace Drive I" planes, currently Pakistan's most capable aircraft, were completed in December under a 2006 contract. The contract, including the 18-plane option, was then valued at $3 billion. RELATED TOPICS Asia & Pacific Rim Air Warfare A planned upgrade to F-16A/B Block 15 aircraft will bring them up to the Block 40 standard as well. They are currently being put through the Falcon STAR (Structural Augmentation Roadmap) program, and undergoing Mid-Life Update (MLU) at the hands of Turkish Aerospace Industries in Turkey. In 2006, the value of 60 MLU kits was quoted as $1.3 billion. The upgrade was approved for 45 Block 15s, and now has been curtailed at 35 planes, Khan said. The reason for this is uncertain. Khan notes that U.S. Navy has refused to release 14 ex-Pakistani F-16s that were part of the "Peace Gate III/IV" order of 71 planes. These aircraft were embargoed before delivery under the Pressler Amendment in the 1990s and eventually found a home with the Navy's aggressor units. The news of curtailment in the F-16 upgrade program comes a week after it was reported the upgraded aircraft will be equipped with the ITT Systems AN/ALQ-211 (v)9 Advanced Integrated Defensive Electronic Warfare Suite (AIDEWS) electronic warfare pod. The $49,097,182 firm fixed price Foreign Military Sales contract will provide systems software and support equipment 18 pods, four pod shells, two antenna coupler sets, two lab test benches, and data. There may also be new equipment for the Pakistan Navy. Khan said there was no news as of yet on acquiring additional pair of P-3C Orion maritime patrol aircraft to replace those destroyed in the May 22 terrorist attack on PNS Mehran in Karachi. However, there was a very strong possibility another Oliver Hazard Perry class frigate would be transferred to Pakistan when it was retired from USN service later this year.