When I first got into the hobby we flew open exhaust control line and glow fuel fires happened a lot from priming the exhaust port. One fire was caused by a very well known local pylon racer who also happens to work for the Seattle Fire Dept and to make a long story short we had to call the trucks
2 other guys on the scene of the crime were fire alarm system installers.
Dry grass, no water, blankets or fire extinguishers.