The number of Indian Air Force (IAF) squadrons required is decided based on various factors like threat perceptions, security concerns and operational requirements of the IAF and is reviewed from time to time.
In the last five years (Financial Years 2005-06 to 2009-10), 48.3% of the accidents in the IAF were due to Technical Defects, 37.9% were due to Human Error and 8.6% were due to Bird Hit.
The IAF has a well structured strategy in place for life extension of existing aircraft fleet by the Original Equipment Manufacturer (OEM) and also by Indian agencies like Hindustan Aeronautics Ltd. (HAL), National Aeronautics Ltd. (NAL), etc.
This information was given by Defence Minister Shri AK Antony in written reply to Prof Anil Kumar Sahani in Rajya Sabha today.