I spent 12 fun years on AirUK and KLMUK maintenance at NWI. From trying to prevent a F50 prop from turning during start up (Trying to locate an engine fuel leak but with hindsight a stupid thing to do) to using reverse pitch on a ground run on an F50 to deliberately soak the outside guy with surface water. I had a funny moment on a F100 engine run once. The post maintenance EGR on the F100/F70 could take all day sometimes. I was usually the outside man and I used to take the ramp van across so to get some respite from the elements. At the time we used the threshold of disused runway 22 for EGR's. We started the runs and I did all the external engine adjustments which took a couple of hours. The cockpit guys had loads of other functionals to do so I parked the van close to the nose and I sat in the van with the headset/long lead connected through the window. After another couple of hours I must have dozed off. When I woke up, the engines were still running so I hadn't missed much...... or so I thought. I looked to my left out the van window and was surprised to see a RAF Gazelle parked up about 100 metres away. Good God I thought. How did I not hear that land. I then turned my head to the right and I was shocked to see the entire Red Arrows team parked up in a neat line starting 70 metres from my van. I really must have been quite far gone.... oops.