The only RFM that I have seen a running take off recommended was in a 1958 model 'H' Bell 47 with a Franklin engine. When I test flew it in 1978 after an engine change I found out why. This machine was very challenged in the vertical performance department.
Running take offs are a 'limited power' technique and whether you fly a skid machine or wheels don't mess with running take offs unless you have been shown how to do it properly.
For public transport ops you need to ensure you can at least achieve an in-ground-effect hover. If your Tq in-hand is zero you had better be sure you are on a runway or a big field. 5% is a good minimum to work with and 10% ideal. I've thrown pax out before now if the site is a bit on the tricky side. I go back for them later of course - well some of the time anyway.
G
