There are problems with the fuselage, with cracks being detected in the lower fairing skin. This is an area that is most affected by G or gravity-related pressures

It is Pakistan's frontline fighter, warplanes to take on the Rafale. It is also one of China's principal jets along with the J-20. As it should be, as it is a joint production effort by China and Pakistan. 

Latest reports from the government sources show that about 40 per cent of JF-17 fighters in two Pakistan Air force bases are grounded for a variety of reasons. And there is no quick fix for the problems as they relate to structural issues.

The JF-17's canopy electrical system is malfunctioning. This is also the case in the JF-17B, the dual seater. This is a potential danger as it makes ejection by the pilot in case of it being required either difficult or almost impossible.

There are problems with the fuselage, with cracks being detected in the lower fairing skin. This is an area that is most affected by G or gravity-related pressures.

There have been cracks in the strake areas, which could be in the fuselage or wings. A strake is a strengthening device and again, this could be because of stress during flying. 

There are also cases of anchor breakages in the JF-17. This is another sign of structural weakness. The radar and it's attached equipment is heavy and is clearly too heavy for that part of the fighter, sources said.

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