Definition(s)
Landing String
All the equipment of the riser above the tubing hanger that is contained wholly or partly within the BOP stack and up to the first standard riser joint. NOTE For live well operations, the landing string typically consists of a tubing hanger running tool, subsea test tree, shear sub, retainer valve and lubricator valve. For killed well operations, the landing string typically consists of a tubing hanger running tool and tubing hanger orientation joint or slick joint.
Source: API RP 17G, Recommended Practice for Completion/Workover Risers, Second Edition, July 2006 (Reaffirmed April 2011). Global Standards
Landing String
Jointed pipe used to run casing strings, liners, or tubing. NOTE A landing string can be designed to have a higher load capacity and is often inspected to a higher acceptance criterion than a string used for drilling.
Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards