Land and Hold Short Operations (LAHSO) - Operations which include simultaneous takeoffs and landings and/or simultaneous landings when a landing aircraft is able and is instructed by the controller to hold-short of the intersecting runway/taxiway or designated hold-short point. Pilots are expected to promptly inform the controller if the hold short clearance cannot be accepted.
Source: FAA JO 7110.65 Air Traffic Control
LAHSO is a procedure used mainly in the USA. If it is to be used by ATC in the USA, the FAA requires that the runways involved have:
- A hold short line on the landing runway prior to the intersecting runway or taxiway
- Holding position signs on both sides of the runway adjacent to the runway hold lines.
- A sign with a white inscription on a red background is installed adjacent to these holding position markings.
Pilots receiving and accepting ATC LAHSO instructions in the form "Clear to land Runway 'AA', Hold Short of Runway 'BB'," must either exit Runway 'AA', or stop at the holding position prior to runway 'BB'.
Under FAA rules, ATC may authorise LAHSO on a dry runway only if the following conditions are also met:
- The runways are reported as clear and dry
- Weather is better than 1000 ft. ceiling and 3 miles visibility with no tailwind
- Instructions are issued that restrict aircraft from entering the intersecting runway or taxiway being used by other aircraft
- Traffic information is acknowledged by the pilots of both aircraft
- The distance from runway threshold to the intersection involved is provided to the flight crew on request
- The distance from the landing threshold to the intersection is assessed as adequate for the landing aircraft category.
Related FAA rules require that if the runway is wet, ATC may only authorise LAHSO if the following additional conditions are also met:
- The airport concerned holds a specific approval for particular runway/runway or runway/taxiway combinations
- The runway pavement surface and friction measurements comply with criteria established by the FAA
- Runway braking action is reported as good
- The runway is not reported as contaminated.
Under FAA procedures, pilots are not required to accept a LAHSO clearance but if they do, the pilot-in-commands are expected to satisfy themselves that their aircraft can safely land and stop within the Available Landing Distance, which ATC will provide upon request. If landing long becomes likely, then a go around or rejected landing is expected rather than the possibility of violating a LAHSO clearance.
It should be noted that some non-US airlines specifically prohibit the acceptance of LAHSO on safety grounds based upon their operational risk assessment procedures.