Spaceflight Now: Delta launch report

GPS 2R-5 launch timeline
Posted: July 14, 2000

T-00:00.0 Liftoff
The Delta 2 rocket's main engine and twin vernier steering thrusters are started moments before launch. The six ground-start strap-on solid rocket motors are ignited at T-0 to begin the mission.
T+01:03.0 Ground-Lit SRM Burnout
The six ground-start Alliant TechSystems-built solid rocket motors consume all their propellant and burn out.
T+01:05.0 Air-Lit SRM Ignition
The three remaining Alliant TechSystems-built solid rocket motors strapped to the Delta 2 rocket's first stage are ignited.
T+01:06.0 Jettison Ground-Lit SRMs
The six spent ground-started solid rocket boosters are jettisoned in sets of three at T+66 and T+67 seconds to fall into the Atlantic Ocean.
T+02:11.5 Jettison Air-Lit SRMs
Having burned out, the three spent air-started solid rocket boosters are jettisoned toward the Atlantic Ocean.
T+04:27.1 Main Engine Cutoff
After consuming its RP-1 fuel and liquid oxygen, the Rocketdyne RS-27A first stage main engine is shut down. The vernier engines cut off moments later.
T+04:36.1 Stage Separation
The Delta rocket's first stage is separated now, having completed its job. The spent stage will fall into the Atlantic Ocean.
T+04:41.0 Second Stage Ignition
With the stage jettisoned, the rocket's second stage takes over. The Aerojet AJ118-K liquid-fueled engine ignites for the first of two firings needed to place the upper stage and GPS 2R-5 satellite into the proper orbit.
T+04:57.0 Jettison Payload Fairing
The 9.5-foot diameter composite payload fairing that protected the GPS 2R-5 satellite atop the Delta 2 during the atmospheric ascent is jettisoned is two halves.
T+10:59.2 Second Stage Cutoff 1
The second stage engine shuts down to complete its first firing of the launch. The rocket and attached GPS 2R-5 spacecraft are now in a 9-minute coast period before the second stage reignites.
T+20:00.0 Second Stage Restart
Delta's second stage engine reignites for a short firing to continue the journey to space.
T+20:37.0 Second Stage Cutoff 2
The second stage shuts down after a 37-second burst. Over the next minute, tiny thrusters on the side of the rocket will be fired to spin up the vehicle in preparation for stage separation.
T+21:30.0 Third Stage Ignition
The liquid-fueled second stage is jettisoned from the rest of the Delta 2 rocket having completed its role in the launch. The Thiokol Star 48B solid-fueled third stage is then ignited to complete GPS 2R-5's delivery into its intended orbit around Earth.
T+23:32.5 Third Stage Burnout
Having used up all its solid-propellant, the third stage burns out to completed the powered phase of the launch sequence. Over the next two minutes, two small yo-yo-like structures are released from the third stage to reduce the spinning motion the Delta rocket and GPS 2R-4 are experiencing in preparation for satellite separation.
T+25:27.0 GPS 2R-5 Separation
The U.S. Air Force's NAVSTAR Global Positioning System Block 2R-5 spacecraft is released into space. The Delta should have placed the satellite into a transfer orbit with a high point of 10,998 nautical miles and low point of 101 nautical mile. The satellite will circularize its orbit.

Data source: Boeing.
Flight Data File
Vehicle: Delta 2 (7925)
Payload: GPS 2R-5
Launch date: July 16, 2000
Launch window: 0917-0943 GMT (5:17-5:43 a.m. EDT)
Launch site: SLC-17A, Cape Canaveral, Fla.

Pre-launch briefing
Orbit trace - A map shows the launch track for the mission.

Delta 2 rocket - Overview of the Delta 2 7925-model rocket used to launch GPS satellites.

Global Positioning System - Description of the U.S. Air Force's space-based navigation network.

GPS constellation - Chart shows the current status of the orbiting GPS satellite fleet.

Flight profile
profileTrack the major launch events for the Delta 2 rocket carrying the GPS 2R-5 satellite on Spaceflight Now's interactive flight profile page (requires JavaScript).