Turnbacks were (are) routinely practiced by QFI/QPNIs at Linton in the Tucano. You needed to have achieved a speed/height combination (130kts/500ft from memory). Without this you simply did not have the energy to complete the manouvre
and still have the energy to safely eject if needed!
Options available included a 'dumb-bell' back on to the reciprocal, or a less agressive turn onto finals for another runway. The former involved a hard turn (45aob), invariably away from any crosswind (to help blow you off the centre-line) prior to a swift reversal onto the the reciprocal. (A bit like a procedural turn!). In the Tucano a top-tip was to take mid-flap ASAP to arm the stick shaker and give a slight increase in performance. Needed plenty of awareness re: speed, height , bank, ROD, seat parameters etc. The aim was simply to see if a safe landing could be made rather than jettisoning the aircraft! Landing ahead in a field was not recommended.
Another option was to simply fly a 180 as discussed by others, but this was rarley practiced due to relative position of the ac v runway. It was only an option when the ac was well upwind or had more energy when you could glide ahead for a few seconds prior to initiating the turn.
Take-off brief included details about the turnback to be flown if required. You needed to think about the planned departure; you were often planning to turn at 500ft anyway, so this needed to be included in the turnback plan. Have heard some people call it a turnback only if you go for the reciprocal rather that an alternate runway.
Finally...
There's no loss of airspeed turning out of a headwind to a tailwind. If there were, you couldn't fly a 360 at height without constantly changing attitude to maintain a constant speed, 'cause there's head and tail wind there as well.
However, if you turn back in these circumstances your groundspeed increases markedly (by 2 x windspeed once you've completed 180 degrees). As all this is happening close to the ground, and is thus very noticeable, the natural tendency is to pull off the apparently excessive speed. Result, tears all round.
I'm with JF - I don't agree! Wish I could prove it with the numbers, but I can personally testify that, in a light/slow aircraft, a slick turn onto a downwind trk
will temporarily reduce your IAS and not instantly increase your gnd speed.
