I still claim newbie status, so the idea of hot fueling had never entered my mind.

however, risk management is something I am familiar with to a limited extent with full size aircraft, in my vocational part time career, and in my day job.

People speed in cars and get away with it most of the time. When they don't it hurts.

People drive too fast in fog and get away with it most of the time. When they don't it hurts.

In either of the above situations, when people get hurt a raft of justitified critique hits the guilty party, they are shown to have unnecesarily increased the risks, and have paid consequences as a result.

There may be good reasons for hot fueling, and if the risk of an incident can be managed to the least level, and the most likely consequence is safety and success, then I suppose it is acceptable. There are some very experienced people on here, who am I to disagree?

However, spilled fuel is dangerous, not just from a flashpoint and fire perspective, but, I recall reading the review of a Facet trainer in RCJI that had to have an emergency landing as spilled fuel killed the ECU but not immediately.

What would you say to a jet liner that took off having been overfilled with kerosene, and the fuel dripped off the plane on take off, would you be happy? But what is the difference between that and a model??

I am not sure what temperatures the full size aircraft work at, but is the exhuast efflux a similar temperature to ours?

I recall the horrifying last flight of the Concorde. If the temperatures are similar, then whilst I do agree the worst thing about kerosene is the smell rather than the flash point, but just consider what could happen.

Now if hot refueling is done with the right procedures and with the risks fully appreciated and managed, then in theory it should be OK. BUT there is clearly more risk involved, temperature, moving parts etc etc, so if it is not necessary, then it should be avoided in my humble view.

For me, the only hot fuelling I could really envisage is the overflow tank to increase the air time following start up, but even then I am not sure about the real advantages.

No offence to anyone, not trying to be a killjoy!

Gazzer