Ares I crew launch vehicle first-stage: NASA’s prime contractor ATK speaks

by | Mar 31, 2008 | Constellation | 1 comment

The following text is my expanded notes from my 28 February 2008 interview with Alliant Techsystems’ (ATK) space launch systems’ vice president Mike Kahn at the company’s clearfield offices in Utah.

The [Ares I crew launch vehicle] resonant burning, oscillation is due to the variation of the width of the thrust channel. The exhaust gas flow through that varying pitch generates perturbation. Garry Lyles [NASA Marshall Space Flight Center’s engineering associate director] will issue a report [on oscillation] at the end of March. [Question is] will the shaking attenuate with the upper stage, what is the upper stage’s natural frequency? The first-stage natural frequency changes as the burning goes on. The [first-stage’s] frustrum could be a dampner.

Caption: A CGI movie of what could be the Ares I-X test scheduled for April 2009
Note: this is not an ATK movie I found it on Youtube and thought it applicableGimbaling on Ares I slightly less than Shuttle, gimbles couple of degrees, thrust vector control (TVC) is the same [system]. [The TVC is] designed for more than that, higher thrust [from the nozzle] means smaller degree of change for [change of velocity].

The current system uses hydrazine for TVC actuators’ hydraulics. Our goal is…can we replace hydrazine with something else. Helium is one option. [We] want to change what powers TVC hydraulics. The question they are asking is, what is the right one and when do we introduce it [and] what is lower cost? [The] safer replacement will reduce life cycle costs because we can remove the controls and precautions that are costs.

There is a system tray to connect the TVC to the first-stage avionics in the upper stage.

[For] composite [casings the] trade [is] on processing and building [it], [we would] use metal connectors for each [composite] casing, segment. The more performance composite would set you up for a larger internal pressure [for more thrust].

[With five segments] more surface area means more propellant burning and more pressure. [It is] not just [the number of] fins but how deep they are.

The extra segment does mean higher separation and as the [Pratt & Whitney Rocketdyne] J-2X is not as capable as the Space Shuttle Main Engine, [it] resolved that less thrust [from the J-2X].

We did consider introducing nozzle extension for resolving increased weight of new Ogive [Sears-Haack] shape to the [Orion crew exploration vehicle] boost protection cover.

We are still burning for 120s, we will just get to 70nm faster. Extra segment just means more propellant so more thrust. [We reach] max-q at about 60s [into the ascent].

The composite frustrum helped us to meet the mass margin. We were within target weight by a few thousand pounds. Our [target weight] became easy because the higher thrust [from five segments] offset mass targets.

Ares I allows natural flow from Shuttle to Ares V. It is important to have Ares V discussions now. Doing Ares V at the right time is important for everyone.

About Seradata

Seradata produce the renowned Seradata database. Trusted by over 100 of the world’s leading Space organisations, Seradata is a fully queryable database used for market analysis, failure/risk assessment, spectrum analysis and space situational awareness (SSA).

For more information go to

Related Articles

Italian government gives Vega C vote of confidence with a three-launch order for its IRIDE constellation

Arianespace has won a contract for up to three Vega C launches for the IRIDE, the Italian government's Earth observation Read more

NASA uses CLPS programme to contract lunar ride for Firefly’s Blue Ghost 2 lunar lander and ESA’s Lunar Pathfinder comms relay spacecraft

Firefly Aerospace has been awarded a second CLPS transportation order to the Moon, this time for the Blue Ghost 2 Read more

NASA unveils new spacesuits for Artemis astronauts moon landing

A new style, for a new space era - that's the message NASA wants to send with the unveiling of Read more

SATELLITE 2023: Regional GEO operators talk about LEO constellation threat.. don’t think its the end of the world yet

During a Tuesday afternoon panel at the SATELLITE 2023 conference, Washington DC, the representatives of large regional GEO operators discussed Read more

SATELLITE 2023: Updates on Project Kuiper and surprise antennas reveal

For the Tuesday opening keynote talk at the SATELLITE 2023 show in Washington DC, Dave Limp, the Senior Vice President Read more

Raytheon gets US$250 million contract to build missile-tracking satellites for Space Development Agency

Raytheon Technologies has secured a contract valued at over US$250 million from the US Space Development Agency (SDA) to build Read more

SpaceX launches Crew-6 to ISS

Endeavour, a Crew Dragon spacecraft carrying four people for NASA's Crew-6 mission, is on its way to the International Space Read more

Rivada Space places US$2.4 billion order for 300 satellites with Terran Orbital, but ITU deadline looms

On 21 February, Rivada Space Networks GmbH contracted American manufacturer Terran Orbital to produce 300 satellites in the 500 kg Read more




nasaspacexecoreviewsissesaArianespacevideochina25virgin galacticfalcon 9ULARoscosmosDGAaviation weekaressoyuzIGTevaFalcon 9v1.2FT Block 5spacewalkBeidouawardsInternational Space StationspaceSatellite broadcastingBlue OriginrussiamoonStarlinkCargo Return VehicleresearchboeingmarsblogAirbus DSOneWebRocket LaborionISROimpacthyperbolamarsdelayjaxaspaceshiptwodemocratgoogle lunar prizerocketlunarhypertextobamaEutelsatlaunchVegatourismconstellationbarack obamafiguresSESnorthspaceflightnode 2fundedRaymond Lygothales alenia spaceIntelsat2009romeAtlas VExpress MD-2dassault aviationss2Elon MuskaviationLucy2008wk2Lockheed Martinukradiotestmissilesuborbitaldocking portexplorationsstlVirgin OrbitinternetChina Manned Space Engineeringsts-122Ariane 5 ECASLSmissile defensenewspapercotsgalileospace tourismflight2010Ariane 5Express AMU 1spaceportbuildspace stationaltairElectronshuttleProton Minternational astronautical congressNorthrop GrummanIntelsat 23Cosmosscaled compositesEuropean Space AgencyLauncherOnehanleybudgetrulesnew yorksoyuz 2-1aLong March 2D/2shenzhouAriane 6atvspace shuttleVietnamLong March 4CcongressMojaveboldenOrbital ATKiacGuiana Space Centercnesnew shepardLong March 2CUK Space AgencyksclawsSpace Systems/LoralprotonUS Air ForceILSInmarsatLong March 4BTalulah RileyApollodarpaeuSkylonAstriumlanderdragonbaseusaastronautpictureeventSSLfivelunar landerfalconSea LaunchWednesdayinterview50thSNCAprilVega CKuaizhou 1ASpace InsuranceTelesat7customeratlantisLong Marchlinksuccessorgriffin