What is "srvl"

Shipborne rolling vertical landing (SRVL) is a method used to land a V/STOL aircraft that uses both the vertical thrust from the jet engine and lift from the wings.

A V/STOL aircraft normally either lands vertically or it makes a conventional runway landing. For a vertical landing it uses downward thrust from the lift fan and/or rotated jet nozzle(s), while for a runway landing the jet nozzle(s) are pointed rearward. With a rolling vertical landing the aircraft uses downward jet thrust to hover while it is still moving fast enough to also generate wing lift. This allows for a rolling landing with a significantly reduced approach speed and landing distance.

With an SRVL manoeuvre, a V/STOL aircraft can make a rolling landing on an aircraft carrier and come to an effective stop with the disc brakes in the landing gear. Unlike a conventional rolling landing on a carrier, this does not require the use of an arrestor wire and tailhook. The operational advantage of this technique is that it can increase the landing payload capacity of a V/STOL aircraft, which can be restricted when it lands vertically. It can also reduce the level of wear on the lift engines and extend their operational life. Similarly, it can reduce the amount of wear upon the deck surface of a carrier caused by the downward jet exhaust from vertical landings.