tail can hit the ground and the aircraft comes up. or during landing it can occur as well. a tail strike typically occurs during takeoff when you're getting too aggressive about your climb and your vr, rotating speed, is anticipated and you start to rotate before the aircraft clears the ground. >> that goes to maintenance record, finances of the company, that's why this speculation about whether or not they were paying the pilots factors into the analysis. the point of the heat signature, i want to make sure it doesn't mean. when it came out, it sounded like they have proof that something fired up from the ground and left a heat signaturic strooing the plane. that's not what it means at all, yes? >> no, not at all. missiles can be launched without the pick up of this infrared signature. the infrared signature has to be something very significant. it's not just the temperature, chris, it's the rate at which the temperature changes that creates this ir affect. if it's quick and a long drawn out one like a missile launch,