A launch status check, also known as a "go/no go poll" and several other terms occurs at the beginning of an American spaceflight mission in which flight controllers monitoring various systems are queried for operation and readiness status before a launch can proceed. For space shuttle missions, in the firing room at the Launch Control Center, the NASA Test Director (NTD) performed this check via a voice communications link with other NASA personnel. The NTD was the leader of the shuttle test team responsible for directing and integrating all flight crew, orbiter, external tank/solid rocket booster and ground support testing in the shuttle launch countdown. The NTD was also responsible for the safety of all personnel inside the pad after external tank loading, including the flight crew. He reported to the Launch Director. The Launch director declares if a mission is go for launch.
OTC – Orbiter Test Conductor PrimeTBC – Tank/Booster Test Conductor and Tank/Booster Test Conductor PrimePTC – Payload Test ConductorLPS – Launch Processing System Test ConductorsHouston Flight – Flight Director at the Christopher C. Kraft Jr. Mission Control Center in Houston, TXMILA – Merritt Island Spaceflight Tracking & Data Network StationsSTM – Support Test ManagerSafety Console – Safety Console CoordinatorSPE – Shuttle Project EngineerLRD – Landing and Recovery DirectorSRO – Superintendent of Range OperationsCDR – Mission Commander (Crew)In the Apollo program, the MCC launch status check was initiated by the Flight Director, or FLIGHT. The following "preflight check" order was used before the launch of Apollo 13:
BOOSTER – Booster Systems Engineer (monitored the Saturn V in pre-launch and ascent)RETRO – Retrofire Officer (responsible for abort procedures and Trans-Earth Injection, or TEI, retrofire burns)FIDO – Flight Dynamics Officer (responsible for the flight path of the space vehicle)GUIDANCE – Guidance Officer (monitored onboard navigational systems and onboard guidance computer software)SURGEON – Flight Surgeon (directs all operational medical activities)EECOM – Electrical, Environmental, and Consumables Management (monitored cryogenic levels, and cabin cooling/pressure systems; electrical distribution systems)GNC – Guidance, Navigation, and Control Systems Engineer (responsible for the reaction control system, and CSM main engine)TELMU – Telemetry, electrical, and EVA MOObility OfficerCONTROL – Flight ControllerPROCEDURES – Procedures, or Organization and Procedures Officer (enforced mission policy and rules)INCO – Integrated Communications OfficerFAO – Flight Activities Officer (checklists, procedures, etc.)NETWORK – Network (supervised ground station communications)RECOVERY – Recovery Supervisor (coordinated capsule recovery)CAPCOM – Capsule Communicator (communicated with the astronauts)Varies depending on the type of mission and model of craft, here is one example:
CLCDRTalkerTimerQAM1 - Quadrature amplitude modulationQAM2QAM3FSCProp 1Prop 2PTO - Payload Test ConductorACCLWOAFLC - Air Force Logistics CommandLaunch Vehicle DirectorEndeavour Go For Launch (STS-123)STS-122 Go/No Go Poll (STS-122)STS-115 Atlantis long countdown to launch (launch status check at 3:03) (STS-115)Space Shuttle STS-114 Launch Final Poll (STS-114)Go For Launch Part 1 of 2 (2 examples launch director's poll)Go For Launch Part 2 of 2 (example final readiness poll)Space Shuttle Launch Countdown (NASA Transcript from 1995) 
