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Hypersonic Airplane Space TetherOrbital Launch (HASTOL) Study

NASA Institute for Advanced ConceptsSecond Annual Meeting

Goddard Space Flight CenterGreenbelt, Maryland

June 7, 2000

John E.GrantThe Boeing Company

5301 Bolsa Ave., Huntington Beach, CA 92647-2099+1-714-372-5391

john.e.grant@boeing.com www.boeing.com

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Presentation Outline

• Team Acknowledgments• HASTOL Concept of Operation• Phase I Results

– Hypersonic Airplane– Tether Boost Facility– Tether– Payload Capture

• Phase II Plan• Follow-On Efforts

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HASTOL Phase II Study Team

The Boeing CompanyJohn Grant, Reusable Space Systems, Huntington Beach, CAJim Martin, Reusable Space Systems, Huntington Beach, CA

Tom Bogar, Phantom Works, St. Louis, MODon Johnson, Phantom Works, St. Louis, MOJoe Stemler, Phantom Works, St. Louis, MOMike Bangham, Space and Communications, Huntsville, ALBen Donahue, Space and Communications, Huntsville, ALBeth Fleming, Space and Communications, Huntsville, ALBrian Tillotson, Space and Communications, Seattle, WA

Tethers Unlimited, Inc.Rob Hoyt, Seattle, WABob Forward, Seattle, WA

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The HASTOL System Concept of OperationFeatures a Reusable Launch Architecture

• Hypersonic Airplane Carries Payload up to 100 km, Mach 12• Rendezvous with Tip of Rotating Tether in Orbit• Tether Lifts and Tosses Payload into Orbit or Escape

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HASTOL Phase I Results ShowedConcept Feasibility

• Top -Level Requirements Developed; Top-Level TradesConducted to Define Basic Design Approaches

• Selected Hypersonic Aircraft Concept (DF-9)

• Validated Overlap of Tether Tip and Hypersonic AircraftVelocity and Geometry Envelopes for Capture

– Defined Aircraft Apogee Altitude/Velocity Envelope

– Tether Tip Can Withstand Thermal Loads as it Dips intothe Atmosphere

• Tether Boost Facility Concept Defined

• Rotovator Tether Concept Selected

• Simplified Grapple Concept Identified

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HASTOL Baseline Hypersonic Aircraft Concept:Boeing-NASA/LaRC DF-9 Dual-Fuel Aerospaceplane

Takeoff Wt: 270 MT (590,000 lb)Payload: 14 MT (30,000 lb)Length: 64 m (209 ft)Apogee: 100 km

Speed at Apogee: 3.6 km/sec(approx. Mach 12)4.1 km/sec(inertial)

Turboramjets up to Mach 4.5Ram-, Scramjets above Mach 4.5Linear Rocket for Pop-Up Maneuver

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Aircraft “Pop-Up” Mission Profile Analysis ShowsRequired Speed and Altitude are Attained

Launch Ascent

High Speed ClimbMach 4.5 - 10

Pattern, Landing,Post FlightOperations

Alternate UpperStage to TetherRendezvous

DescendDecel

Tanker RendezvousInflight Refueling

BallisticTrajectory to

TetherRendezvous

Initial ClimbMach 0.8 - 4.5

SubsonicCruise

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❍ ❍

❍ ❍ ❍

250,000

300,000

350,000

400,000

8,000 9,000 10,000 11,000 12,000

2,500 3,000 3,500Veloc ity

m/s

ft/s

80

90

100

110

120

Alti

tude

kmft

Achievable Po ints

Unachievable Po ints

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• DF-9 - Horizontal takeoff, horizontal land concept– Developed by Boeing for NASA LaRC– Derivative of DF-7 hypersonic cruise airplane concept

• Hyper-X (X-43) - Scramjet flight test vehicle from Pegasus booster– Microcraft prime contractor; Boeing subcontractor– First flight test vehicle delivered; flight to Mach 7 in Sept 2000– Second flight test vehicle to be delivered to NASA in August 2000– Third flight test vehicle in design/fab; will fly to Mach 10 in Oct 2001

• X-34 - Rocket boosted hypersonic flight demo– Being developed by Orbital Sciences– Captive flight tests completed– Phase 1 flights to Mach 3.8; Phase 2 flights to Mach 8

• X-33 lifting body, aerospike engine– Being developed by Lockheed-Martin– Flight vehicle being assembled; testing to Mach 10+ envisioned

• X-37 (Future-X) Hypersonic research test bed vehicle– Boeing/NASA MSFC Cooperative Effort– First flight planned for 2003 (Shuttle payload); re-entry to powerless

horizontal landing

Ongoing Hypersonic Aircraft Development ProgramsWill Benefit HASTOL Concept Maturity

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HEFT Tether Boost Facility is Adaptableto the HASTOL Mission

Facility center of mass inslightly elliptical orbit: - 700 km apogee - 610 km perigee - 90 km from tether station - 7.6 km/sec perigee velocity

Tether: - Length: 600 km - Tip velocity: 3.5 km/sec - When facility center of mass is at perigee, tether tip is at100 km altitude

Station Mass: 1,650 MTTether Mass: 1,360 MTGrapple Mass 650 MT

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Solar P anelA rray

1,000- to 2,000-tonneTether C ontro l S tation

600-kmSpectra2000Tether

G rapp le W inch

Zylon (PB O )G rapple Tether

G rapp le

yloadcom m odationsem bly

G rapp leA ssem bly

G rapp le

G rappleTether

Tether D ep loym ent and R etrieval M echan ism

H ousing fo r Tether R ee l, A vion ics, R C S Fue l, B atteries, and B attery R echarging C ircu its

G rapp le A ssem bly

Prim ary L ines

S econdary L ines(In itia lly U nstressed)

F irst Leve lof SecondaryLinesTransfersLoad A roundD am agedSection Second Level of

Secondary L inesR edistribu tesLoad B ack onU ndam agedPortion ofP rim ary L ine

E ffects o fD am ageLoca lized

Tens ofM eters

H oytether D esign

Space Tether Fac ility

20-md iam eter

C ut P rim ary L ine

HEFT Tether Boost Facility is Adaptableto the HASTOL Mission

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The Hoytether™ Design will survive meteorite strikecuts or material failure of primary lines

Primary Lines

Secondary Lines (initially unstressed)

0.2 to 10's of meters

0.1- 1 meter

Severed Primary

Line

Effects of Damage Localized

a. b.

Second Level of Secondary Lines Redistributes Load Back to Undamaged Portion of Primary Line

First Level of Secondary Lines Redistributes Load to Adjacent Nodes

c.

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Rotovator™ Tether and Hypersonic AirplaneRendezvous occurs at 100 km, 4.1 km/sec

0

20

40

60

80

100

675 700 725

Tether Tip

Temperature(C)

750 775 800 825 850Time (s)

0

50

100

150

200

675 700 725 750

Tether Tip

Altitude(km)

775 800 825 850Time (s)

TETH-1017

Center-of-MassVelocity

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Phase I Results Show Feasibility ofPayload Capture

• Tether-Payload Rendezvous Capabilityis a Key Enabling Technology

• TUI Has Developed Methods forExtending Rendezvous Window– Works in Simulation– Validation Experiments Needed

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Simplified Grapple Approach Selected for Phase I

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Other Grapple Concepts Have Been Investigated;Baseline Approach Will Be Revisited in Phase II

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2

3Attach Levers then move radially outward toward ring; sliding on rails. Once contact with ring is made, they latch to the ring securing the payload to the grapple.

Grapple / End mass comes down on Payload

Payload Surface

Grapple stops on Payload, levers on payload are in "in-close" position

Grapple Ring

GRAPPLE TO PAYLOAD ATTACHMENT OPTION Radially moving Levers move to ring and secure P/L

Barbed Grapnel

1. Cable with tipgrapnel flies by tether

2. Tether tip lifts upward,grapnel snags cable.

vTether

v

Tether

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HASTOL Phase II Study Tasks

• Mission Requirements and Mission OpportunityDefinition

• System Requirements• System Concept Definition• System Analysis• Technology Development Roadmap

(near term demos)

• Contract Schedule/Key Milestones:• First 12 of 18 month program funded• Concept Definition and System Analyses will be

nearly complete by end of 12th month

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HASTOL Phase II Study Schedule

TETH-1010

2000Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2001Task Names

1. Mission OpportunitiesDefinition (SOW 1.0)

2. System RequirementsDefinition (SOW 2.0)

3. Conceptual Design(SOW 3.0)

4. System Analysis(SOW 4.0)

5. TechnologyDevelopment Planning(SOW 5.0)

Program ManagementProgram Managementand Reporting

ReportsMonthly ReportsMidterm ReportFinal Report

Program Reviews NIAC AnnualMeeting

NIAC Fellows’Conference

Final Program Review

Program Kick-off

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HASTOL Phase II Study Approach

Task 1 M iss ion O pportunities D efin ition• D eve lop con tact p lan• C onduct k ick-o ff w ith po ten tia l custom ers and N IAC• M ee t w ith custom ers to assess poten tia l m issions

and nea r-te rm app lica tions• Iden tify oppo rtun ities to in tegra te in to N A SA

prog ram s

• D erive pre lim ina ry system requ irem ents fo r each o fthe HA ST O L system s

• D ete rm ine payload cha racte ristics, tra ffic ra te ,gu idance and con tro l, g -fo rce lim ita tions, in itia l and lifecycle costs , and system in te rface requ irem en ts

• Iden tify, de fine , a lloca te , and trade m a jo r systemrequ irem en ts

Task 2 System R equirem ents D efin ition

Task 3 C onceptual D esign• In teg ra te in to system arch itectu re• C onduct trade stud ies• D eve lop R O M cost estim a te

Task 4 System A nalys is• C onduct m ode ling and sim ula tions• C onduct p re lim ina ry techn ica l assessm ent - Iden tify h igh-risk areas - D eve lop m itiga tion p lans

Task 5 Technology D eve lopm ent P lann ing• Iden tify techno logy needs• D eve lop techno logy deve lopm ent roadm ap - F ligh t test p lan - Labo ra tory tests

H yperson ic A irp lane S pace Tether O rb ita l L aun ch (H A ST O L) S tud y P rogram , P hase II

P hase I R esults• R o tova to r concept• T echno logy Read iness Leve l 2 system s (hype rson ic a irp lane , te ther con tro l sta tion , te ther, g rapp le assem b ly, payload accom m oda tion assem b ly)• T rade study resu lts: d iscove ry tha t rendezvous po in t can be ach ieved by existing airp lane (X -43) w ithou t ove rhea ting te the r tip• S e lected concep ts - D F -9 hype rson ic veh ic le - R endezvous po in t a t M ach 10 , 100-km a ltitude- H oyte therTM w ith Spectra2000T M m a te ria l and PB O tip m a te ria l

C and ida telist o fm issionneeds

• F ina l P hase II p rog ram review• P hase II fina l repo rt

– S ystem requ irem ents– C om p le te system design concep t to TR L 3– A reas o f deve lopm en t w ork needed– Techno logy roadm ap– C ost m ode ls

• P hase III custom er fund ing com m itm en t

P hase II D eliverab les

– A na lyze key techn ica l issues✔ G N & C✔ P ayload transfe r opera tions✔ Te ther design and dynam ics✔ M ateria l se lection✔ S im u la tion resu lts

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System Analysis Tasks Address Areas of Concern

• Detailed rendezvous and payload capture simulation will identifypayload grapple requirements

• Abort modes will be investigated -- what if payload is not captured?

• Payload release orbits

• Cost modeling -- compare HASTOL to other launch systemarchitectures

• Tether dynamics and associated interaction with grapple assembly

• Tether material survivability in space environment

• Electrodynamic thrust control for reboost and orbit transfer

• Collision avoidance of known orbiting assets

Technology Development Roadmap will identify near term demonstrations needed for low risk flight demonstration.

Technology Development Roadmap will identify near term demonstrations needed for low risk flight demonstration.

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Roadmap Identifies Stepwise Technology Demonstrationand System Development, Production and Deployment

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200404

200505

200606

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200808

200909

201010

201111

201212

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201414Task Names

TETH-1023

Plasma Motor GeneratorSEDS-2TSS-1RTIPSISS Tether ReboostProSEDS

Applicable Tether Experiments

Applicable Hypersonic AircraftContracts

Dual Fuel Vehicle StudyHyper-X Flight Test ProgramDual-Role Vehicle StudyAirbreathing Launch Vehicle Study

Boeing / TUI Contracts

MMOSTTHASTOL

Follow-on TechnologyDemonstrations

Typical Technology Demo No. 1Typical Technology Demo No. 2Typical Technology Demo No. 3

Operational System

Phase 1Phase 1

Phase 2Phase 2

PrototypeDemonstrationProgram

OperationalSystemProduction

OperationalSystemDeployment

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Additional Near-Term Studies Can AssessFeasibility and Identify Key Flight Demos

• Automated Rendezvous & Capture– Time Window for Capture < 10 Seconds– High Accuracy Requirements

• Electrodynamic Tether Operation– High Power & Voltage Issues– Control of Tether Dynamics

• Traffic Control/Collision Avoidance• Economic Analysis/Business Plan

– Technology Risk Reduction– Incremental Commercial Development Path– Customer Acceptance

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Near-Term Flight Experiments will ValidateFeasibility for Prototype System Development

• Spinning Tether Orbital Transfer System - STOTS– Deploy Small Payload on a Tether– Demonstrate Spin-Up of Tether System Using Reeling– Demonstrate Controlled Toss of Payload– Build on SEDS Heritage– Piggyback on Delta II Launch

• Tether Orbit Raising Qualification Experiment - TORQUE– Deploy Hanging Tether Below Small Facility– Demonstrate Payload Rendezvous & Docking with Hanging Tether– Demonstrate Electrodynamic Spin-up of Tether– Demonstrate Controlled Toss of Payload– Demonstrate Electrodynamic Reboost of Facility– Perform Repeated Boosting of Commercial/Scientific Payloads

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Tether Systems Have the Potentialto Enable Low Cost Access to Space

• Concept feasibility study already completed.• Key targets for technical risk reduction have been

identified.• Tether experiments have already flown in space.• Planned near term experiments further reduce

potential system risks.• Phase II analyses will reveal near term demonstrations

and flight experiments required for full scale systemdevelopment.

• Modest near term government investment isencouraged to fund demos and experiments.