I do not know whether Pumas still have them but in the 70s Pumas had blue night formation lights mounted on top of the sponsons and doghouse.
One night we tried night formation with just NV goggles and formation lights. You could hold position quite easily. The fomation lights gave you a good reference coupled with the shape of the aircraft and as you were looking down the jet exhaust the power turbine lit up like a beacon. Unfortuately the rest of the crew were having kittens.............