framer / gorter, re energy/speed #21 –
Whilst the energy discussion is physically / mathematically correct, it may not be relevant when considering a fixed landing distance.
Where a decision to land is made on a particular length runway as adjusted for wind, any increase in flight speed over that used in the calculation will affect the distance required / safety margin; – the distance required to dissipate the increased energy vs that planned. And this involves V*V.
From a certification aspect the operational landing distance is often based on a fixed flare time and speed loss from Vref, e.g. 7 sec and -7kts; actual certification distances may differ from this.
Vref is usually the basis for the approach speed, e.g. Vref+5, but this speed should be considered as a target not a minimum. If the approach speed is considered a minimum, accepting speed variations above the target, then the net approach speed will be higher and thus this increment should be considered in the landing distance required (~300ft/10kts).
Many operators add speed and buffers for an approach and landing, but few actually consider the distance / safety effects, nor adjust the landing distance required.
As for landing technique; IIRC it involves matching height-rate against height for the time / speed loss as above, with a target residual height-rate at touchdown.