launch kit 157 en

7/29/2019 Launch Kit 157 En

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FLIGHT 157 L517 - ARIANE 5 10 tonnes

S o m m a i r e

1. INTRODUCTION .............................................................................................................

2. LAUNCH VEHICLE L517................................................................................................

3. THE PAYLOAD...............................................................................................................

4. THE LAUNCH CAMPAIGN.............................................................................................

5. THE LAUNCH WINDOW.................................................................................................

6. FINAL COUNTDOWN.....................................................................................................

7. FLIGHT SEQUENCE.......................................................................................................

8. FUTURE ..........................................................................................................................

9. EADS LAUNCH VEHICLES AND THE ARIANE PROGRAMMES


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1. INTRODUCTION

Flight 157 is the 1st launch of an Ariane 5-plus (10 tonnes), the 14th ARIANE 5 launchand the 11th ARIANE launch for the year 2002.

Flight 157 is the 11th commercial mission of the Ariane 5 launch vehicle, Flight 157 is alsothe qualification flight of the version A5ECA of Ariane 5-plus launch vehicle, with the thirdcryogenic stage ESCA. For these two reasons, this flight is managed by Arianespace.

This mission comes after the successful qualification flights (V502 in October 97 and V503in October 98) conducted under the care of ESA and CNES, and after 10 successfulcommercial flights among which 9 successes between December 99 and August, 2002(Flight 510 ended in the stake with post on degraded orbit by satellites Artmis and BSAT-2B in July, 2001).. However, since this date, Artmis was able to reach the geostationaryorbit thanks to its Ionic engines.

Launch vehicle 517 is the 12th production vehicle, operated under Arianespacesresponsibility.

In a multi-payload launch configuration with SYLDA A (1,500 mm elongated) under longNose-Fairing, its carrying the HOTBIRD 7 telecommunications satellite in top position, andthe French technological satellite STENTOR in bottom position.

HOTBIRD 7, built by ASTRIUM

Is placed under the Ariane 5 long fairing built by OERLIKON-CONTRAVES

On an adaptater937VB5 built by EADS-CASA

itself put on 1 MFD-A (Modular Fitting Dummy oftype A) built by KAISER-THREDE

STENTOR built byASTRIUM & Alcatel SpaceIndustries

Is placed inside the SYLDA 5 A built byASTRIUM

on an adapter1194 V5 built by EADS-CASA

itself put on a MFD-B (Modular Fitting Dummy oftype B) built by KAISER-THREDE

HOTBIRD 7belongs to a very regular customer of Ariane: EUTELSAT.

Arianespace Operations Directorate is conducting integration, inspection, operation andlaunch. The launch is from ELA 3 (dedicated Ariane 5 pad).


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2. LAUNCH VEHICLE L517

Launcher description

It is composed of an upper composite mountedon the top of the EPC stage including:

Stage ESCA of Ergols Cryogenic,

The Vehicle Equipment Bay,

The cone 3936

The SYLDA 5 payload carrier structure,

The Payload Fairing.

The lower composite, built by EADS LAUNCH VEHICLESincludes:

The main cryogenic stage (EPC) (H 175),

Two identical solid propellantboosters (EAP)(P240), secured laterally to the EPC.

Capacity of the sub-system liquid Helium

Main Cryogenic Stage :

More than 30 metres high, 5,4 metres in diameter, and weighing only 14,2 metric tonsempty, the EPC consists essentially of:

a large aluminium alloy tank, a thrust-frame transmitting the engine thrust to the stage, a front skirt linking the EPC to the upper composite and transmitting the thrust of the two

solid propellant boosters.


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LUNCH VEHICLE L517 (CONTINUED)

With regard to the basic stage of Ariane 5 version, the main evolutions concern theintegration of the Vulcain 2 engine (which the thrust is upper of 20 % to that of the Vulcain1 engine ) which was accompanied by the lowering of the common bottom of the tank andin an intensification of the front skirts structures and thrust frame.

The tank is divided into two compartments containing the 175 tons of propellants (about 25tons of liquid hydrogen and 150 tons of liquid oxygen). Its Vulcain 2 engine delivers a thrustof the order of 135 tons and is swivel-mounted about two axes for control, with the engineactivation unit (GAM). This stage is ignited on ground, where its operation is first checkedbefore authorising lift-off.

The stage operates continuously for 540 s, providing the essential part of the impulse needed

for injection into orbit.

At burnout, which occurs at an altitude of between 130 and 420 kilometres, depending on themission, the stage separates from the upper composite and falls back into the ocean.

Solid Propellant Boosters:

Each of these stages is more than 31-m high, 3 m in diameter, has an empty mass of 40 tonsand contains 240 tons of solid propellant. These boosters consist essentially of:

an envelope of seven steel cylindrical shells, a flex-mounted nozzle (pressure ratio = 11), with the nozzle activation unit (GAT) the propellant in three segments

The EAPs are ignited 7s after the Vulcain engine. The thrust they deliver varies in time, (600tons at lift-off, which is about 90 % of the total thrust). They burn for about 130 s and are thenseparated from the EPC by pyrotechnic cutting and fall back into the ocean. For the mission517, both EAP are equipped with a kit which will allow to collect them after functioning, thento estimate them.

With regard to the the basic stage version Ariane 5, the main evolutions concern thedeletion of a bottle GAT, the over load of the segment S1 increasing the thrust by takeoffand the use of a relieved nozzle.


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LAUNCH VEHICLE L517 (CONTINUED)

A new Cryogenic Upper Stage, type A:

The 3rd stage ESCA was recently developed for the version A5ECA of the Ariane 5launch vehicle more around the engine HM7B, taken of the 3rd stage of Ariane 4.

The mission of the ESCA is to provide additional energy necessary to place payloadsinto the aimed orbit. The stage also assures through the SCAR (System of Control ofAttitude and Roulis) the control of roulis of the upper stage during the propelled phaseand the orientation of the payloads for their separation in ballistic phase.

It consists of:

two tanks containing 14,6 t of ergols (liquid hydrogen and oxygen),

the engine HM7B delivering a 6,5 t trust in vacuum, and which has a burning time

of about 950 s. Its nozzle is swivel-mounted on two axes, for control.

Vehicle Equipment Bay:

The VEB consists of a cylindrical structure above the ESCA, containing a part of the electricalequipment needed for the mission (2 OBCs, two new defined inertial units, sequentialelectronics, power supplies, TM with UCTM-D),

For information, the basic stage of Ariane 5 version contains a metal structure and

integrates the attitude control system (SCA).

The thrust frame of Ariane 5 ESC-AThe first equipped thrust frame ESCA, delivered on

February 13, 2002 to Astrium Gmbh in Breme, Germany.Copyright : EADS-LV.

Ariane 517 10 tonnes launch vehicle, after RAL(Launch readness review) transfered to the launch

complex ZL3 in Kourou, Frech Guiana Ds23230ESA/ARIANESPACE/Service optique CSG


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Payload Fairing :

The bullet-shaped payload fairing protects the payloads during atmospheric flight (acousticprotection at lift-off and in transonic flight, aerothermal fluxes).

For this mission, a longPayload Fairing is used. It is 17 m high and 5.4 m in diameter.

It consists of two half fairing of ten panels. These panels are made of sandwich structure withperforated, expanded aluminium honeycomb core and two skins of carbon fibre/resin.

Two pyrotechnic devices one horizontal (HSS) and the other vertical (VSS) separate thetwo half fairing. The vertical device imparts enough impulse to the separated fairing to clearthem away laterally.

SYLDA 5 (Ariane 5 Dual launch system):

This is one of the six versions of this internal structure, 4,6 m in diameter. They vary in heightfrom 4,9 to 6,4 m (in steps of 0,3 m) offering usable volumes from 50 m3 to 65 m3. Thissystem makes it possible to carry a second main payload in one of the three fairing models.

For this mission, a SYLDA A version (6,4m high) will be used.


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The mission

The main mission of flight 157 is to inject orbit:HOTBIRD 7 et STENTOR into a specificgeostationary orbit:

Apogee altitude 35786. km

Perigee Altitude 250. km

Inclination 4.

Perigee Argument 178.

Ascending node -124.5 (*)

(*)With regard to a fixed axis, frozen to H0 - 3s and passedby the launch complex ELA3 in Kourou, Guyana.

HOTBIRD 7 weighs 3,350 kg and STENTOR 2,230 kg. Including the masses of the adapters,the SYLDA, and so on, the total mass the launch vehicle is expected to launch into the orbitdescribed above is 8,390kg.


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Description of diffrent flight phases

The time reference being H0 (the moment when the EPC Vulcain engine hydrogen valve isopened) the Vulcain engine is ignited at H0 + 2.7 s. Its nominal operation authorises ignitionof the two solid propellant boosters (EAP) at H0 + 7.05 s, causing launch vehicle lift-off.

The launch vehicle mass at lift-off is about 780 metric tons, and the initial thrust is 12,800 kN(90 % of which is provided by the EAPs).

After a vertical ascent of 5 seconds to clear away from the ELA 3 (mainly from the lightningpylons), the launch vehicle begins a tilting in the plane of trajectory and, 5 seconds later, aroll manoeuvre to place the plane of the EAPs perpendicular to that of the trajectory.

The EAP flight continues at zero angle of attack, throughout the atmospheric phase, up toEAP separation.

The purpose of the manoeuvres is:

to optimise the trajectory to maximise performance

to provide satisfactory radio link budget with ground stations

to meet in-flight structural loading and guidance constraints.

The EAP separation sequence is triggered when an acceleration threshold is detected, atthe time the solid propellant booster thrust drops off. Actual separation occurs in the secondfollowing this event.

This time is referenced H1. It occurs at about H0 + 137.8 s, at which point the altitude is 68,9km, and the relative velocity 1,921 m/s.

For the rest of the EPC flight, the launch vehicle follows an attitude law controlled in realtime by the onboard computer with input information from the navigation unit, whichoptimises the trajectory to minimise combustion time, and thus propellant consumption.

The nose-fairing is jettisoned during this EPC flight as soon as the aerothermal fluxes aresmall enough to be withstood by the upper payload.


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The EPC guided flight aims at a pre-determined orbit, set by safeguard requirements.

The Vulcain engine is shut down, when the orbit characteristics are:

Apogee altitude 2147.0 km

Perigee altitude -1321.9 km

inclination 6.796

Perigee argument -39.397

Ascending node longitude 125.402

This is time refenrence H2.

The "ESCA" powered flight phase, that follows, lasts a little more than 15 minutes andterminates on order from the onboard computer when it estimates (calculating on the basis ofinformation from the inertial unit) that the aimed orbit has been reached.

This is time reference H3.

The following ballistic phase has the following purposes:

Aim the composite in the direction required by HOTBIRD 7, and then by STENTOR, (theirorientations for separations are bound to the position of the Sun for their requirementssatellites, thus dependent on the launch time)

The launchers three-axes stabilisation forHOTBIRD 7,

Spin-up the launcher STENTOR (at 4/s)

SeparateHOTBIRD 7 and STENTOR,

Passivate the VEB pressurised tanks (LOX than LH2 of the ESCA.

While managing inort and middle term the spacing of bodies on orbit


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LAUNCH VEHICLE L517 (END)

The Main Cryogenic Stage (EPC) naturally falls back into the Pacific Ocean after its separation (seebelow), breaking up at an altitude of between 80 and 60 km under the loads due to atmospheric re-

entry.To avoid an explosion of the stage due to the heating of the residual hydrogen, the stage has to bedepressurised. This is called passivation. It is accomplished by using a lateral nozzle on thehydrogen tank, actuated by a delayed relay initiated at the time of EPC separation.This lateral thrust is also used for starting the stage rotation, thereby limiting the dispersions duringre-entry.

The Main Cryogenic Stage (EPC) falls back at an angle of -3,92, and the longitude of the point ofimpact is 5.83 W.

The Kourou, Galliot, Natal, Ascension, and Malindi stations provide visibility during the mission.


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PAYLOAD

HOTBIRD 7

- Programme

The EUTELSAT Company will be operating this satellite, which is ordered from ASTRIUMto supply telecommunications services, essentially between European countries.

By conception, this satellite is compatible with several launche vehicles families: inaddition to Ariane 4 and 5 launched from Kourou, the Atlas II launched from Cap

Canaveral.

HOTBIRD 7, with HOTBIRD 6, is a part of the second generation of the satellitesHOTBIRD that will replace gradually the fleet already in orbit. HOTBIRD 7 will replaceHOTBIRD 3 and offer a possibility of back-up partial for HOTBIRD 2.

HOTBIRD 7 should thusenlarge the fleet ofEUTELSAT satellites, whichis already one of the biggestin the world with servicescovering the entire planet.

Other EUTELSATsatellites are beingmanufactured or are about

to be launched:e-BIRD, W5, W3A,

Expres AM1.

European coverage

American coverage


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PAYLOAD (CONTINUED)

Arianehas already been used to launch manysatellites forEUTELSAT: the series

inaugurated when Eutelsat II F1 was launched on Ariane 4 Flight 38 on 30/08/90, and wasfollowed:

Eutelsat II F2 and F4 (on A44L Flight 41 and Flight 51),

Hotbird I, 3 and 4 (on A44LP Flight 71, A44LP Flight 99 & A42P 1 Flight 06)

Telstar 12 (on A44LP Flight 121)

W2 and W1 (on A44L Flight 111 and A44P Flight 132)

Eurobird (on A5 Flight 140)

Atlantic-Bird 2 (on A44P Flight 144)

Photos by Arianespace

- Mission

HOTBIRD 7 is designed to respond to the increasing demand for next generationdigital direct-broadcast television and interactive services, operating up to 40channels. 39 repeaters operate in the frequency bands of 33MHz and 1 in 49.5 MHz.

The zone of coverage concerns Europe, and it will be offering alle these services withoutstanding operational flexibility. The satellite will have two deployed antennaes thatcan point to all the visible zones of earth since its orbital position.


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PAYLOAD (CONTINUED)


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PAYLOAD (CONTINUED)

- Satellite

HOTBIRD 7 is based on the stabilised three-axis platform EUROSTAR 2000+.

* Dimensions 5.2 x 2.3 x 3.4 metres

* Masse Weight on lift-off 3,350kg

dry 1,530kg

* Power 6 700 W (payload at life end)

* Propulsion orbit control and apogee motor using bi-liquide fuels* Stabilisation 3-axis stabilisation in orbit

Transmission

capacity 40 repeaters in Ku band, band BSS

* Orbital position 13 longitude Est

* Ground coverage Europe

Expected life duration : 12 years

Kourou : Hotbird 7 in the Integration Hall,October 9, 2002Copyright : ESA/CNES/Arianesapce photo : service optiqueCSG


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PAYLOAD (CONTINUED)

STENTOR

- Programme

The projet STENTOR (Satellite de Tlcommunication pour Exprimenter deNouvelles Technologies en Orbite) is an experimental telecommunications satellitesupported by the French Space Agency CNES, together with France Telecom and theFrench Ministry of Defence, DGA. The satellite is manufactured by the IndustrialProject Group ASTRIUM and ALCATEL SPACE INDUSTRIE which are co-primecontactors for the programme.

The mission of the satellite STENTOR is to make demonstration in orbit of the spacetelecommunications technologies developed by the French satellite manufacturers andto improve their competitive position on the international telecommunications market.These new technologies (80 % of the on-board equipment is experimental) concernthe payload (antennaes, digital television, repeaters, EHF service) as well as the plate-form (structure, chemical propulsion, plasmic propulsion, thermical control, orbitalattitude, energy, data management, command and telemetry).

The programme, once the satellite in orbit, is foreseen in two stages:

A 2 year period for technological and system experiments and implementation of

the various payload operating scenarios,

A 7 year period to study and aging process and performance stability of the on-board equipment, and in particular to demonstrate new telecommunicationsservices (point-to-point high-speed transmission, interconnection between differentnetworks, multimedia applications).

- Mission

Coverage zone EHF of STENTOR


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PAYLOAD (CONTINUED)

Exemples of STENTORs coverage zones in Ku band

- Satellite

STENTOR is based on an experimental trois-axes stabilised platform on geostationaryorbit. The satellite uses the strcture of the SPACEBUS 3000 B3.

The thermal control uses the original system containing a fluid buckle with capillarypumping. A deployable radiator allows to increasethe the thermical capacity.

The propulsion used a bi-liquid system with an apogee motor of 400 N thrust and aattitude control system composed of 14 thrust nozzles. Fuel pressurisation is realizedwith a new type of Helium capacity on titane wound carbon.

The satellite also disposed a system of two blocs of Xenon plasmic propulsion. (Thetank is identical to that used for the Helium). The propulsife blocks are 2 axissteerable.


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PAYLOAD (CONTINUED)

For the avionic, the concept used forSTENTOR is based on that of EUROSTAR 3000.

The batteries use Ion-Lithium technology.A GPS is on-board to test possibilities of autonomous positioning.

Payload includes services in Ku bands (3 repeaters and 3 antennaes) and EHF (1repeater and 1 antennae).

STENTORs most considerable elements of the external appendixes (deployed or fix)are:

The broadcast deployable antenna,

The orientable antenna, The active transmission antenna in Ku band,

The fix antenna for EHF band ,

The deployed solar pannels ,

The deployable radiator.


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PAYLOAD (END)

- Technical caracteristics

* Dimensions 4,5 x 3,3 x 2,7 metres

15,6 metres (solar panel span)

* Mass Weight on lift-off 2,230kg

dry 1,186kg

* Power 2,100 W (payload: at life end)

* Propulsion orbit control and apogee motor using bi-liquid fuels(NTO/MMH) and ionic propulsion

* Stabilisation 3-axis stabilisation en orbit

* Transmissioncapacity

3 repeaters in Ku band, in bands with 14 14.25 GHzand 12.5 to 12.75 GHz

1 repeater EHF in the bands of 44 45 GHz and 20.2 to21.2 GHz

* Orbital position 11 longitude West

* Ground coverage Europe and Guyana.

Expected life duration : 9 years


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LAUNCH CAMPAIGN

The Main Cryogenic Stage (EPC)ARIANE 5 in Les Mureaux, Franceoperations in the integration docks,before shipped to the GuyanaSpace CenterCopyright : EADS-LV. photo: StudioBernot

The Main Cryogenic Stage (EPC) loaded in LeHavre on the TOUCAN four Kourou, GuyanaCopyright : EADS-LV. photo: JL

Thrust frame of Ariane 5 ESCA at EADS-LVLes Mureaux, France, before his departure toASTRIUM in Breme, GermanyCopyright : EADS-LV. photo: Studio Bernot


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LAUNCH CAMPAIGN (CONTINUED)

Mayor steps of launch compaign Flight 157are summaraised below:

Removal of EPC from storage and erection in the LaunchVehicle Integration building (BIL)

August, 22

Transfert of solid boosters (EAP) and accosting August ,23 to 27

Removal from storage and erection of ESCA September, 05

Removal from storage and erection of the Paiload Fairing September, 11-12

Flight control check-out and over-all check out September, 25

Tlaunch vehicle transfert from the Integration Building (BIL)

to Final Assembly Building (BAF)

September, 30

Arrival of HOTBIRD 7 in Guyana October, 02

Arrival of STENTOR en Guyana October, 09

1st RSL with transfers BAF ZL October, 11 to 18

2nd RSL with transfers BAF ZL November, 04-07

HOTBIRD 7 filling November, 14

STENTOR filling November, 15

HOTBIRD 7 mated on his adapter November, 15

Integration of the composite (HOTBIRD 7 + ACU) on SYLDA November, 16

STENTOR mated on his adapter November, 18

Integration of the upper composite November, 20

General repetition November, 22

Launch Readiness Review November, 25

Launch Vehicle transfer from BAF to Launch Pad (ZL3) November, 26

1st Final countdown November, 28

General repetition December, 06

Launch Readiness Review December, 06

Launch Vehicle transfer from BAF to Launch Pad (ZL3) December, 06

Final countdown, including EPC and ESCA filling December, 11

The not detection of the correct ignition of the external chill-down igniters (AMEF) stopped theliftoff on November 28th before the ignition of Vulcain engine, but after opening of thecryotechniques arms.

Reconfiguration of Ariane 5, Flight 157 is compleated, the additional RAL was held onDecember 9th, it authorized the reprogrammation of the launch on December 11th.


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LAUNCH CAMPAIGN (END)

Kourou : transfert of the launch vehilce,October 11, 2002Copyright : ESA/CNES/Arianespace photo : serviceoptique CSG

Kourou : Erection of ESC-A, in the LauncherIntegration Hall (BIL) September 5, 2002Copyright : ESA/CNES/Arianespace, photo :service optique CSG

Kourou : September 30, 2002Transfert without fairing from BIL to BAFCopyright : ESA/CNES/Arianespace, photo :service optique CSG


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THE LAUNCH WINDOW

For a launch during the night from Wednesday December 11, to Thursday December 12,2002, with H0 at 10:22 p.m. GMT, the launch window will last 53 minutes:

The launch window will close at 11:14 p.m. (GMT).

The launch window is determined from a compromise between launcher and satelliteconstraints.

UNIVERSAL Time

December 11, 200210:22 p.m. 11:14 p.m.

KOUROU Time

December 11, 20027:22 p.m. 08:14 p.m.

PARIS &DARMSTADTTime

December 11/12, 200211:22 p.m. - 00:14 a.m.


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FINAL COUNTDOWN

This includes all launch vehicle, satellite, and launch base preparation operations needed toallow ignition of the Vulcain engines, then the Solid Propellant Boosters, at the launch timechosen, at the earliest possible time in the satellite launch window. The countdown ends witha synchronised sequence managed by the ARIANE ground checkout computers starting atH0 - 6 min 30s. If a countdown interruption shifts H0 beyond the launch window, the launch ispostponed to D+1 or D+2 depending on the nature of the problem and the time to solve it.

H0 - 7h 30 Check of electrical systems, red indicators, count down time

Flushing, then configuring ofEPC and Vulcain for filling and chilling down.

H0 - 6h Final preparation of launch area : closure of doors, removal of safety

barriers, configuring of fluid circuits for filling

Flight Programmes loading

Test of radio links between Launch Vehicleand BLA

Alignment of inertial guidance platforms

H0 - 5h Evacuation of Launch Pad

Filling of EPC in four phases:

pressurisation of ground stores ( hour)

chilling down of ground lines ( hour)

filling of stage tanks (2 hours)

top-ups(until synchronised sequence)

H0 - 5h Pressurisation of control and command system:

(GAT for the EAPs and GAM for the EPC)

H0 - 4h Filling of ESCA in four phases:

pressurisation of ground stores ( hour)

chilling down of ground lines ( hour)

filling of stage tanks (1 hours)

top-ups(until synchronised sequence)

H0 - 3h Chilling down of Vulcain engine

H0 - 30mn Preparation of Synchronise Sequence d

H0 - 7mn State of pre-synchronization


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SYNCHRONISED SEQUENCE

This starts at H0 - 6 min 30 s and includes all launch vehicle operations leading to lift-off.These operations are controlled fully automatically by the ELA3 Operational CommandControl (CCO). During this sequence, all the means involved in the launch are synchronisedby the "countdown time" distributed by the Guyana Space Centre (CSG).

In the first phase (down to H0-6 s), the launch vehicle is gradually placed in lift-offconfiguration.

In the second phase (down to H0-3.2 s), or irreversible sequence, the synchronisedsequence is no longer dependent on the CSG countdown.

The last phase is the launch vehicle ignition phase.

FLUID SYSTEMS ELECTRICAL SYSTEMS

H0 - 6mn 30 sStopping of top-ups (LOX and LH2)Top-ups of LOX and LH2 to flight valueOpening of launch table flood safety valves

H0 - 4 minFlight-pressurisation of RO2 and RH2 tanksIsolation of tanks and beginning of umbilicalflushing at ground-vehicle interface

H0 - 2 minOpening of Vulcain supply valvesClosure of engine chilling down ground valves

H0 - 30sChecking of ground-vehicle umbilical flushingOpening of flue flood valves

H0 - 18sPressurisation of POGO suppression device

H0 - 2sChecking of EPC tank flight pressures

H0 - 6mn 30 sArming of pyrotechnic line safety barriers

H0 - 3 min 30s

Loading of H0 in two OBCsSwitching of 2nd OBC to observer mode

H0 - 1 minSwitching of EPC control system supply from

ground to vehicleH0 50 s

Switching of launch vehicle electrical supplyfrom ground to vehicle

H0 37 sStart of ignition sequence automatic systemStart of vehicle measurement recordersArming of pyrotechnic line electric safetybarriers

H0 22 sActivation of lower stage control systemsAuthorisation of OBC management take-over


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SYNCHRONISED SEQUENCE

This starts at H0 - 6 min 30 s and includes all launch vehicle operations leading to lift-off.These operations are controlled fully automatically by the ELA3 Operational CommandControl (CCO). During this sequence, all the means involved in the launch are synchronisedby the "countdown time" distributed by the Guyana Space Centre (CSG).

In the first phase (down to H0-6 s), the launch vehicle is gradually placed in lift-offconfiguration.

In the second phase (down to H0-3.2 s), or irreversible sequence, the synchronisedsequence is no longer dependent on the CSG countdown.

The last phase is the launch vehicle ignition phase.

FLUID SYSTEMS ELECTRICAL SYSTEMS

H0 - 6mn 30 sStopping of top-ups (LOX and LH2)Top-ups of LOX and LH2 to flight valueOpening of launch table flood safety valves

H0 - 4 minFlight-pressurisation of RO2 and RH2 tanksIsolation of tanks and beginning of umbilical

flushing at ground-vehicle interface

H0 - 2 minOpening of Vulcain supply valvesClosure of engine chilling down ground valves

H0 - 30sChecking of ground-vehicle umbilical flushingOpening of flue flood valves

H0 - 18sPressurisation of POGO suppression device

H0 - 2sChecking of EPC tank flight pressures

H0 - 6mn 30 sArming of pyrotechnic line safety barriers

H0 - 3 min 30s

Loading of H0 in two OBCsSwitching of 2nd OBC to observer mode

H0 - 1 minSwitching of EPC control system supply from

ground to vehicleH0 50 s

Switching of launch vehicle electrical supplyfrom ground to vehicle

H0 37 sStart of ignition sequence automatic systemStart of vehicle measurement recordersArming of pyrotechnic line electric safetybarriers

H0 22 sActivation of lower stage control systemsAuthorisation of OBC management take-over


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SYNCHRONISED SEQUENCE (CONTINUED)

IRREVERSIBLE SEQUENCE

H0 6 sArming and ignition of AMEFs to burn off hydrogen flowing out when thechamber is cooled at ignition p of Vulcain

H0 5.5 sSwitching of ground information communication bus management to OBC

IGNITION SEQUENCE

H0 3 sCheck of computer statesSwitching of inertial reference systems to flight modeActivation of Helium pressurisationMonitoring of LOX and LH2 pressuresActivation of guidance, navigation and control functions

H0 2 sControl flight-pressurisation of EPC tanks

H0 0,2 s

Check at the latest by the OBC of the acquisition of the reportarm cryotechniques retracted

H0 + 6.65sIgnition of Vulcain engine and checking of operation(H0 corresponds to the opening of the hydrogen chamber valve)

H0 + 6.9 sEnd of Vulcain operation check

H0 + 7.05 sIgnition of two EAPs


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FLIGHT SEQUENCE

temps /H0

(s)

temps/H0

(mn) Event

altitude

(km)

Vabs

(m/s)

Vrel

(m/s)

- - - - EAP/EPC powered flight - - -

7,305 0 07 Lift-off --- 463,2 0

12,336 0 13 Beginning of tilting

manoeuvre0,08 464,2 36

17,05 0 17 Beginning of roll

manoeuvre0,35 472 76

32,05 0 32 End of tilting manoeuvre 2,5 548 217

48,6 0 49transsonic

(Mach = 1)6,8 656 325

65,0 1 05 Pdyn max. 12,6 828 480

110,7 1 51 switch to max

(41,4 m/s2)41,5 1908 1517

137,04 2 17switch to = 6,17 m/s

H168,2 2332 1920

137,82 2 23 EAP Separation 68,9 2333 1921

- - - - EPC powered flight - - - -

187,83 3 08 Nose-fairing jettisoning 113,3 2547 2104

412,8 6 53 Galliot-Natal inter-visibility 211 4781 4305

527,6 8 48 EPC burn-out (H2) 215 7222 6744

533,6 8 54 EPC Seperation 215 7248 6770

- - - - ESCA powered flight - - - -

537,7 9 58 ESCA ignition 215 7250 6773

789,6 13 10 Natal-Ascension Interv 201 7885 7408

1000 16 40 ESCA mid point 207 8484 8006

1091,7 18 12 Ascension-Libreville inter-

visibility229 8752 8273

1471,5 24 32 ESCA (H3-1) burn-out 646 9857 9359


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FLIGHT SEQUENCE (CONTINUED)

temps /H0

(s)

temps/H0

(mn)Event

altitude

(km)

- - - - Ballistic phase - - -

1473,5 24 34 Phase 1 and 2 operations of ratrappageinthe beginning of phase SCAR

650

1479,1 24 39 Phase 3 Beginning of HOTBIRD 7orientation

662

1645,1 27 25 HOTBIRD 7 Separation 1089

Jusqu1885,2

31 25 Phase 5 - manuvre dorientation duSYLDA

1885

1885,6 31 26 SYLDA Separation 1887

1895,6 31 36 Phase 7 orientation before spin up 1923

2140.9 35 41 Phase 8 spin up to 4/s 2876

2141,5 35 42 STENTOR Separation 2879

2151,3 35 51 Phase 10 beginning of composite despin 2919

2171,5 36 12 Phase 11 beginning of ESCA orientation 3001

2364,4 39 25 Phase 12 spin up to 45/s 3806

2374,7 39 36 End of spin up at 45/s 4703

2941,3 49 01 Beginning of ESCA passivation 6275


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THE FUTURE

- Launches in 2002:

As of today launches planned in 2002 are: 8 ARIANE 4s and5 ARIANE 5s.

Seven Ariane 4 launches and three Ariane 5 launches have been carried out to date

After mission Ariane 517, the next Ariane 5 flight at the beginning of2003 (necessarilybetween 13th, and January, 31st) has to be a mission on an Ariane 5 P1+ launchvehicle with the European probe ROSETTA (mission towards two asteroids and acomet)

- The programme A5+

The programme A5+ has for general target the starting of successive evolutions of

ARIANE 5, essentially concentrated on its upper floor. It has to get him, by the end ofthe decade, the possibility of realizing double launches of satellites of the 6 tons classon geostationary transfer orbit (this will be the double capacity of the most successfulversion of an ARIANE 4).

In this frame, the launch vehicleAriane 517 marks an importantmilestone with the qualification ofthe launcher version A5ECA, 1stversion of the Ariane 5+

programme that arrived at the endof development. Here after theversions developed within theprogramme A5+:

Launcher version A5ECA:The 3rd stage is replaced by theESC-A, that will carry the totallaunch capacity of a little more than6 tonnes to about 9.5 tonnes.

Launcher version A5E/S:Diverted directly from the currentlaunch vehicle ARIANE 5 bybringing multiple improvements oneach of the stages.


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At the same time the development of the following version already began. This version,A5ECB, is equipped with an improved 3rd stage, "the Cryogenic Upper Stage of typeB" (ESC-B). A completely new propulsion system will carry in 2007 the performance ofan ARIANE 5 launch vehicle to 12 tonnes in a double launch mission to GTO.

These successive evolutions will allow the launcher ARIANE 5 to preserve thecompetitiveness acquired thanks to its capacity of double launches, by adapting itselfto the evolution of the market of geostationnary satellites, among which the size andmass do not stop growing.


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launch kit 157 en

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