Guys,
Perhaps I can help here on the subject of STOVL bringback.
This has always been a KPP for the F-35B, set so as to stress the STOVL design. The KPP was framed as a requirement to carry out a VL to a ship with a full internal payload of 2 1000lb JDAMs and 2 AIM-120, plus enough fuel to carry out a full IMC circuit and landing.
There are a number of conditions that apply to the calculation of the actual 'VLBB' value, not least the required operating temperature and pressure limits. I can't remember the actual figures (sorry Spaz), but the JSF JORD (which the UK signed up to) used a US Mil Spec definition of a 'tropical day'. That applies to this day, and the F-35B must be able to achieve a VLBB with the specified load on that 'hot day'. The actual VLBB number, though, has changed with changes to a number of other design parameters.
The VLBB target is actually pretty tough, as it also makes a number of pessimistic (or realistic, depending on your point of view) assumptions about achieved engine thrust and weigh growth.
However, in around 2002, the UK requested that LM look at the effect on VLBB when operating at even higher temperatures (and lower pressures), such as those that had been experienced in the Gulf in summer. These studies showed that there would be a shortfall in VLBB when operating outside the requirement, and the studies into SRVL started in around 2003.
So, the F-35B can do a VL with stores 'in the heat'. It just can't do it in 'even more heat'. In those extreme cases, the SRVL is being worked on as a solution, and in my view it's a sensible idea. the F-35B has outstandingly clever and effective control systems that give it very good handling qualities throughout the envelope right through transition, unlike the Harrier. It's also got a decent set of brakes. (again unlike the Harrier) Early assessments by the TPs were quite positive, and indicated a good increase in bring back for quite modest speeds over the deck, especially when the ship supplied a bit of WOD.
Hope this helps
Best regards as ever
Engines