May 5, 1989

A PDF of the actual Users Guide is available: Intertank Users Guide.pdf

The Covers:  The cover photo shows a simulation of the Orbiter just prior to separation from the External Tank and a “Free Flyer” module ejected from a Heavy Intertank Door Pallet. Below is depicted an ejected “Free Flyer” with on board propulsion to attain LEO. The inside back-cover photo shows an ejected module leaving the intertank. Models by Ronald Jones.



1877 Broadway
Boulder, CO 80302
Telephone: 303 444-622 1
FAX: 303 444-7047

Table of Contents

1.0 Introduction
1.1 Launch and Mission Profile
1.2 Additional Use of ETs: UCAR’s Space Phoenix Program
2.0 External Tank Experiment Provisions
2.1 Inter-tank Door Pallet
2.2 Heavy Intertank Door Pallet
2.3 Ejection of Independent Spacecraft
2.3.1 Suborbital
2.3.2 Orbital
2.3.3 Re-entry and Recovery
3.0 Operations
3.1 Ground Operations 3.2 Cost Quotations
3.3 Flight Operations
3.4 Baseline Mission Profiles
3.4.1 IDP Mission Timetable
3.4.2 HIDP Mission Timetable
4.0 Payload Interfaces
4.1 Payload Dimensions and Mass
4.2 Payload Mechanical Interfaces
4.3 Payload Electrical Interfaces
4.4 Telemetry
5.0 Payload Environments
5.1 Thermal
5.2 Pressure
5.3 Vibration
5.4 Acoustic
5.5 Acceleration
5.6 Payload Design and Safety Proof Factors
6.0 Payload Integration Support
Appendix A – Acronyms and Abbreviations
Appendix B – IDP & HIDP Launch Services Form

Figures and Tables

Figure 1. Shuttle System Figure
2. Intertank Compartment Figure
3. Intertank Door Figure
4. Intertank Door Pallet (IDP) Figure
5. Heavy Intertank Door Pallet (HIDP) Figure
6. Intertank Door Pallet with Ejection Module Figure
7. Shuttle System with IDP Position Figure
8. Nominal and Direct Insertion ET Trajectories Figure
9. Typical ET Impact Areas for Nominal and Direct Insertion Launches Figure
10. Intertank Compartment Pressure During Ascent Figure
11. ET Acceleration Re-entry Table
1. Mission Development Schedule Table
2. Standard Cost Quotation Phrases


The National Space Transportation System (Space Shuttle) is America’s most versatile spacecraft, providing unprecedented flexibility in space launch and Low Earth Orbit (LEO) operations. The spacecraft’s large cargo capacity, relatively mild launch environment and return-from-orbit capability enables it to carry out missions which no other U.S. launch vehicle can undertake.
The Space Shuttle flight vehicle (Fig. l), consists of three major elements: a reusable manned Orbiter, an External Tank (ET), and two reusable Solid Rocket Boosters (SRBs).

The Orbiter can transport into LEO a three member flight crew and four additional technical and scientific personnel, and a payload. The payload, weighing up to 55,000 pounds, is transported in the Orbiter’s 15 x 60 foot cargo bay. The Orbiter’s three main engines each develop a maximum thrust of 375,000 pounds at launch. Propellants for these engines are supplied from the External Tank. Each of me two SRBs weigh approximately 1.1 million pounds and produces a lift-off thrust of more than 2,600,000 pounds.

The External Tank serves a dual role: it acts as the structural backbone of the Space Shuttle during launch operations and contains liquid hydrogen (LH2) and liquid oxygen (LO2) propellants for the Orbiter’s engines. The ET is 153.8 feet long and 27.6 feet in diameter. It consists of an oxygen tank with a volume of 19,563 cubic feet, a hydrogen tank of 53,518 cubic feet, and a 5,000 cubic foot unpressurized inter-tank compartment 27.6 feet in diameter and 22.5 feet long (Fig. 2). It weighs approximately 69,000pounds empty and when loaded with propellants at launch weighs approximately 1,660,000 pounds.

1.1 Launch and Mission Profile

In the launch configuration the Orbiter and two SRBs are attached to the ET in a vertical position on the launch pad. At launch, the Orbiter’s main engines, fed liquid hydrogen fuel and liquid oxygen oxidizer from the ET, are ignited first. When verified that the engines have the proper thrust level, a signal is sent to ignite the SRBs. At the proper thrust-to-weight ratio, initiators at the holddown bolts are fired to release the Space Shuttle for lift-off. The Shuttle rises vertically, clears the launch gantry tower in approximately 8 seconds, does a roll maneuver to adjust to the desired orbital inclination, then begins a slow pitch maneuver as it gains altitude and velocity.

The two SRBs are jettisoned after burnout, approximately two minutes after lift-off and 27.5 miles high, and are recovered by means of a parachute recovery system. A homing device on each booster guides recovery craft to it for towing back to shore. The boosters are then refurbished, refueled and made ready for another Space Shuttle flight. The Orbiter main engines continue to burn for between six and seven minutes until the Orbiter reaches an altitude of approximately 57 nautical miles and a speed just short of orbital velocity. At this time the engines are shut down and the ET is jettisoned. During its plunge through the atmosphere, the ET tumbles, breaks up and falls into a predetermined area in the Indian Ocean or in the Pacific Ocean west of Hawaii, depending on the specific trajectory used for the mission.

Following a brief period of coast after the main engines have been cut off and the ET has been jettisoned, the Orbiter fires its auxiliary engines to accelerate to the proper orbital altitude and velocity to carry out the main pan of its mission. After orbital operations are completed, de-orbiting maneuvers are initiated.

The primary Orbiter landing facility is Edwards Air Force Base, with several alternate landing sites available for contingencies. After landing, the Orbiter is towed to ground facilities where any returned payloads are removed. Orbiter refurbishment operations are then initiated to prepare for another launch.

1.2 Additional Use of External Tanks:

UCAR’s Space Phoenix Program The External Tank is presently the only element of the Shuttle system which is not reused. Even before the first Shuttle Flight it was recognized that an ET at 99% of orbital velocity represents a potentially valuable asset. An added velocity increment of approximately 250 feet per second would put an ET in orbit. Even without additional velocity the tank has a kinetic energy, at separation from the Orbiter, of approximately 1.4 x 10(12) foot pounds, and in its free fall back to Earth provides a low-gravity environment for approximately 60 minutes before atmospheric drag causes significant deceleration. In addition, each ET normally contains 8,000 to 20,000 pounds of propellant residuals (oxygen and hydrogen) at engine cutoff.

NASA has funded a number of studies of potential uses in space of External Tanks after they are jettisoned. These include an ET Gamma Ray Imaging Telescope, an ET Aft Cargo Carrier, and an ET Propellant Scavenging System. With possibilities of this type in mind, the University Corporation for Atmospheric Research (UCAR), a 58-university consortium, began in 1985 to explore the feasibility and utility of converting orbiting ETs into scientific facilities for atmospheric, space science, engineering, and commercial research. The concept came to be known as the Space Phoenix Program, symbolizing the group’s determination that the ETs would “rise” from the charred fragments that now mark the end of their journey to the threshold of space. The Space Phoenix Program will establish UCAR and its 58 member universities as the beneficiary of a national trust of converted ETs in space.

As a part of UCAR’s space commercialization program joining government, universities, and the private sector, the External Tanks Corporation (ETCO) was formed in 1986 to secure private financing and provide technical and other management functions. The majority stockholder for the External Tanks Corporation is the UCAR Foundation. In 1987 NASA and UCAR signed a Memorandum of Understanding in which they agreed to work together to realize UCAR’s Space Phoenix Program goals. This was followed by a second agreement, signed in late 1988, setting out the terms and conditions under which NASA would allow UCAR to use initial suborbital ETs. Two-tiered pricing will provide favorable rates to government and university users.


UCAR, through the External Tanks Corporation, will now commence to place small payloads in the ET intertank compartment for launch into suborbital trajectories. User equipment will be carried in a proprietary pallet, designed to replace the current ET intertank door (Fig. 3) on selected flights. This approach allows complete experiment and accessory packages to be constructed, qualified and flown with a minimum impact on Space Shuttle operations.

2.1 Intertank Door Pallet

A proprietary Inter-tank Door Pallet (IDP) design with structural and thermal properties similar to the existing intertank door is presently under development (Fig. 4), and will be available to carry small payloads in 1991. The IDP provides a modular, flight-qualified container with self-contained power and telemetry systems to support a wide range of scientific and engineering experiments. Experimental equipment will be independently constructed and qualified, and then integrated into an IDP. The IDP plus payload will then be qualified, and installed in an External Tank at Kennedy Space Center (KSC) during the final stages of pre-launch preparation. This avoids delays that would result if the experiment package were installed at the External Tank manufacturing facility, or in the Orbiter Processing Facility at KSC.

2.2 Heavy Intertank Door Pallet

Larger and heavier payloads will be carried in a Heavy Intertank Door Pallet (HIDP), which includes struts connected to the intertank wall (Fig. 5). Attachment of an HIDP primary structure and its support struts will be accomplished in the Vehicle Assembly Building prior to Shuttle stacking. Independently developed and qualified payloads will be integrated with HIDP secondary structure and supporting systems. The checked out assembly will be installed in the HIDP primary structure during final intertank preparation before launch.

2.3 Ejection of Independent Spacecraft

An independent spacecraft module, independently constructed and qualified, can be ejected after MECO by spring action from an IDP or HIDP (Fig. 6). The intertank door is located 34″ from the “z” axis, opposite the Orbiter, (Fig. 7), providing an ejection path away from the Orbiter before the External Tank is jettisoned. Modules can be ejected into suborbital trajectories, or they can be equipped with boosters to provide transfer to orbit.

2.3.1 Suborbital

Independent modules can be ejected from an IDP or HIDP into suborbital trajectories. Ejected modules will spend up to 75 minutes in space. The modules can be equipped for re-entry and recovery.

2.3.2 Orbital

Ejected modules can be equipped with thrusters to provide transfer to orbit. Initial module coordinates and velocity vector can be determined from the Orbiter coordinates and velocity vector. Because MECO occurs at 99% of orbital velocity, the additional velocity needed to transfer an ejected module from the suborbital External Tank trajectory to LEO is relatively modest.

2.3.3 Re-entry and Recovery

A number of re-entry recovery capsules under development can be accommodated by the IDP or HIDP. The system would allow recovery of suborbital payloads, or recovery of independent spacecraft boosted into orbit after ejection from an IDP or HIDP. Re-entry and recovery systems will be equipped with flotation and a locator beacon. Suborbital recovery capsules will be picked up in the Indian Ocean or the Pacific Ocean, depending on the External Tank launch trajectory (Figs. 8 & 9). Re-entry recovery capsules can also be used for data and film recovery.


In order to minimize the impact of ET pallets and their payloads on the Shuttle, and on the interval between experiment concept and flight, both the IDP and HIDP and their systems are designed to have minimum interfaces with Shuttle systems. As a general rule, pallet and experiment systems will not be activated prior to receipt of an enable command associated with separation of the ET from the Orbiter. Electrical and down-link telemetry will be provided by pallet systems. A limited environmental instrumentation package will be provided as a pallet system. Experiment unique deployment requirements will be negotiable. Active thermal cooling will not be provided for early missions although space exposure of a radiating surface will be considered on selected missions. Standard payload attachment fittings will be provided as shown in Fig (TBD). Payload peculiar harnesses between user and pallet systems will be custom designed and provided by ETCO as an element of integration.

3.1 Ground Operations

Standardization of user interfaces and services, and the use of pallets and pallet systems which have been designed to isolate the IDP and HIDP from the ET and other Shuttle elements, makes it possible to significantly reduce the time interval between experiment concept and launch. Table 1 shows, for a minimum complexity payload pallet interface example, a “no later than” schedule of the major plans, agreements, documents, specifications, and deliveries leading to launch. More complex installations will require appropriate schedule adjustments.
Both analytical and physical integration of experiment systems into the pallet will be performed by ETCO. User participation is expected and, in some cases, will be required. Pre-launch checkout, performed at KSC, will be managed by ETCO, but users will be responsible for providing equipment required for checkout of user-provided flight hardware and software (if any), will participate in the check-out and will verify the results obtained. Following checkout, installation of the pallet in the ET will be managed by KSC personnel or their contractors. User representatives will be expected to participate in a number of ETCO/NASA mission coordination meetings and reviews during the year preceding launch.
Approximately seven months prior to launch a meeting will be held to establish relative ETCO/User requirements and responsibilities for post flight data processing. To the first order, ETCO will strip out and provide to individual users tapes of all data pertinent to their experiments as well as environmental data of use to their analyses.
The following captions provide a summary of the context and purpose of the documents, meetings, and activities included in the Mission Development Schedule:

  • The initial meeting provides for an exchange of data between ETCO and a prospective user in sufficient detail to allow the user to prepare a requirements document and understand the ETCO plan for hazard elimination or containment and for ETCO to initiate the studies necessary to lead to a mission assignment.
  • The Preliminary IDP/User Requirements document will be prepared by the user and identifies all of the available data on user systems which will impact or place demands on the IDP. These demands will include, but will not be limited to structural, electrical, data, RF, thermal, command, and special handling provisions. The information contained in this document will be used to initiate analyses and design efforts required in preparation of interface specifications, hazard analyses, systems integration and mission planning.
  • The Preliminary Hazard Identification will be used as input to the hazard analysis.
  • The mission assignment will be made by ETCO and will result from a best fit analysis incorporating all of the requirements.
  • The Preliminary IDP/User interface specifications will include physical functional, and operational interfaces and will be jointly developed by ETCO and the User.
  • The Preliminary Mission Operations Plan will include a verbal description, agreement on responsibilities, and a detailed schedule of actions and events through post-flight data distribution.
  • The User Structural and hazard analyses will be performed by the user and as input to the overall IDP/Payload analyses.
  • Firm User power and RF requirements will be the basis for final design of IDP support provisions.
  • Firm IDP/User interface specifications will be the basis for final analyses, test and checkout provisions and will be a controlled document.
  • The Final Mission Operations Plan will update the preliminary plan, will reflect previously published firm requirements and specifications and will be a controlled document.
  • The block of activity identified for IDP/User integration and checkout will provide or completion of all known IDP/payload effort required prior to delivery of the integrated IDP to KSC with no open items.
  • Final checkout and integration into the ET includes check-out and acceptance, at KSC, of the integrated IDP, installation in the ET intertank, and required post-installation tests.

These represent principal events, documents, and milestones. There will be other meetings with and submittals to NASA in which ETCO will have principal responsibility, but which will also involve IDP users.

3.2 Cost Quotations

Table 2 presents ETCO’s cost quotation phases following an expression of interest by a potential user for the provision of technical assistance to users during the payload evaluation, mission assignment, integration, qualification and launch activities contemplated by the Mission Development Schedule in Table 1. Following the completion of a Launch Services Request form (Appendix B), and the initial requirements meeting, ETCO will submit to qualified users a detailed Launch Services Proposal which will detail the tasks and activities to be accomplished by the user and ETCO preparatory to launch Rough Order of Magnitude (ROM) cost estimates will be provided for each mission development phase on a time and materials basis. When approved by both parties, these cost estimates will be incorporated along with a more detailed work statement in a Launch Services and Technical Assistance Agreement.

3.3 Flight Operations

The mission itself begins with release of the Shuttle SRB holddown bolts. IDP environmental instrumentation, timers and data recorders are the only IDP user systems planned to be operating prior to Shuttle Main Engine Cutoff (MECO). An arming relay, commanded either by a signal from the ET, a timer, or an accelerometer, will enable commands to be made and executed from the IDP master timer. No externally generated RF commands are planned. The IDP master timer can execute discrete user commands. Although users are encouraged to incorporate their own timers or sequencers to simplify IDP/User interfaces, desires regarding exposure to the external environment, deployment mechanisms, and release of liquids or gases should be brought to the attention of ETCO as early as possible. Users should recognize that support of this type will normally require nominal extension of the Mission Development Schedule.

The normal method for data recovery is for on-board data storage during most of the mission, with data dump late in the mission to a ground station located in the Pacific. Details regarding data stream formats, multiplexing, data rates, etc. are not yet available. ETCO will shred out data for distribution to individual users along with timing and environmental data which is needed by the user.

3.4 Baseline Mission Profiles

The IDP is being designed for compatibility with any External Tank. It can be integrated into a Shuttle mission with reasonable leadtime and minimum impact. The HIDP will require more planning and leadtime because of the installation of the HIDP support struts (Fig. 5). Shuttle flights incorporating the IDP or HIDP will be selected from NASA’s Payload Flight Assignments. The current (January 1989) assignments are listed below. Launch profiles (nominal or direct insertion) have not yet been announced for these missions, but most of them are expected to be direct insertion launches.

45* 160 28.5 2-21-91
46 ** ** 3-28-91
47*** 135 57.0 5-02-91
48 160 44.0 7-01-91
49 160 28.5 8-01-91
50 291 57.0 10-10-91
51 160 28.5 11-14-91
52 160 44.0 12-19-91
53 160 28.5 3-02-92
54 160 28.5 3-30-92
55 160 57.0 5-07-92
56 160 28.5 5-28-92
57 135 57.0 6-l 1-92
58 160 39.0 7-16-92
59 190 28.5 8-13-92
60 160 28.5 9-03-92
61 160 28.5 9-25-92
62 160 28.5 10-22-92
63 **  **  1l-l0-92
64 160 28.5 12-14-92
65 160 28.5 l-l1-93
66 160 57.0 2-1 l-93
67 160 28.5 3-22-93
68 160 28.5 4-12-93
69 160 57.0 5-06-93
71 160 28.5 6-24-93
72 160 28.5 7-15-93
73 160 28.5 8-12-93
74 ** 28.5 9-02-93
75 160 ** 9-30-93
76 160 28.5 10-21-93
77 160 39.0 11-11-93
78 ** 28.5 12-09-93
79 160 ** 1-13-94
80   28.5 2-03-94
81 TBD 28.5 2-24-94
82 160 28.5 3-24-94
83 160 57.0 4-14-94
84 160 57.0 4-14-94
85 160 28.5 5-12-94
86 160 44.0 6-09-94
87 160 28.5 7-14-94
88 160 57.0 9-22-94

* Tentative first IDP launch opportunity
** DOD launch
*** Tentative first HIDP launch opportunity

Table 1. Mission Development Schedule:

Months Before Launch Event
12 Launch request and initial meeting
10 Preliminary User requirements and hazard identification

Mission assignment
Preliminary Pallet/User interface specificationPreliminary Mission Operations Plan

7 User structural and hazard analyses
Final User power & RF data requirements
6 Final pallet/user interface specifications
4 Final Mission Operations Plan
1 Integrated Pallet Delivered to KSC
Final Checkout & Integration into the ET


Table 2. Standard Cost Quotation Phases:

Pre-phase Event
Phase I User expression of interest.
Phase II ETCO issues preliminary mission evaluation & ROM cost estimates.
ETCO and User jointly define Requirements & identify hazards.
Phase III

ETCO final Mission assignment and definition of structural hazard, power & RF requirements.
ETCO issues final Pallet/user interface specifications and Phase V, VI & VII cost estimates

Phase IV ETCO and user finalize mission operations plan.
User systems Pallet Integration and checkout.
Phase V ETCO supervised final checkout and ET integration.
Phase VI  
Phase VII  

Phase VI:

Phase VII:

3.4.1 IDP Mission Timetable

The first IDP launch opportunity is targeted for early 1991 (STS-45). A typical IDP mission timetable is outlined below.

Time   Event
T-7 Days  Final checkout of IDP payload
T-2 Days IDP installed in intertank


T+8.5 Min MECO (110 km altitude; 28,300 km/hr)
Electrical signal to activate payload
T+8.6 Min ET jettisoned from Orbiter
T+46 Min ET reaches apogee
T+60 to 70 Min Telemetry downlink
T+78 Min  ET begins re-entry, 110 km altitude
T+83 Min  ET reaches maximum deceleration of -10 g
  Ejection of data recovery capsule
   ET breakup at 45 – 55 km
T+92 Min Data capsule splashes into ocean
Data capsule transmission begins
T+2 Hour Data capsule located
T+l Day Data capsule recovered

3.4.2 HIDP Mission Timetable

The first HIDP launch opportunity is targeted for mid- 1991 (STS-47). A typical HIDP mission timetable with an ejection payload is outlined below.

Time   Event
T-4 to 6 Weeks HIDP primary structure installed in intertank
T-7 Days  Final checkout of integrated HIDP payload
T-2 Days  

 Payload installed in HIDP primary structure

T-O  Launch
T+8.5 Min MECO (110 km altitude;28,300 km/hr)
  Electrical signal to activate payload
               Independent Spacecraft ejected from HIDP
T+8.6 Min  ET jettisoned from Orbiter
T+15 Min  Spacecraft boost to orbit
T+46 Min  ET reaches apogee
T+78 Min   ET begins re-entry
T+83 Min ET breakup at 45 – 55 km


4.1 Payload Dimensions and Mass

  Payload     Height   Width Depth Volume
Carrier Mass (kg)   (in)   (in)  (in)   (cu ft)
IDP    90 42 48 12 14
HIDP 454  38 44 40 38.7

4.2 Payload Mechanical interfaces

The IDP and the HIDP have standard patterns of mounting bosses for the attachment of payload components or payload secondary structure. Users will have primary responsibility for structural analyses of user supplied components and systems. ETCO will review and approve user analyses and will perform integrated system analyses.

4.3 Payload Electrical Interfaces

The IDP and HIDP will provide battery electrical power to users. One flight qualified battery currently under consideration provides approximately 0.5 KwH with a peak current capacity of 18 Amperes. Multiple batteries can be used. Power conditioning and distribution will be provided as a payload integration service. Electrical harnesses employing standard space qualified connectors will be used throughout.

4.4 Telemetry

A telemetry system consisting of S-band flight and ground hardware capable of handling anticipated data rates will be available as standard IDP and HIDP equipment, The flight system consists of an antenna system, transmitter, power supply, nominal 4 MEG onboard memory, signal conditioners, and a representative suite of sensors. The ground systems are S-band tracking receivers.


Payload environments in the inter-tank have been measured during previous launches and are characterized below. Measurements of the External Tank environment afterMEC0 have not yet been made. However, inter-tank, IDP, and HIDP environments will be characterized by measurements taken during the first IDP and HIDP launches.

5.1 Thermal

The thermal environment of the inter-tank in the vicinity of the intertank door before and during launch is indicated below. The intertank is purged with warm nitrogen gas until just before launch to maintain a temperature of 33 – 120 degrees F. The intertank skin temperature during ascent in the vicinity of the intertank door does not exceed 130 degrees F, but cools down rapidly in space, particularly if it is not illuminated by the Sun.

Time     Degrees F
Prelaunch 33 – 120
Liftoff   80 – 100
Maximum  130

5.2 Pressure

During ascent, gas pressure in the intertank compartment drops from sea level ambient to less than 1 psi in 140seconds (Fig. 10).

5.3 Vibration

Maximum intertank vibration levels during launch before SRB jettison have been measured in previous missions and are indicated below.

Sinusoidal Vibration Limits:
Longitudinal Axis  2 – 40 Hz at 0.6 g peak
Lateral Axis  2 – 40 Hz at 0.8 g peak
Maximum Random Vibration Come
Lift Off   29.6 radial (g rms) 21.0 tangential (g rms)
Boost  26.7 radial (g nns) 17.7 tangential (g rms)

5.4 Acoustic

Maximum acoustic levels in various intertank locations during launch before SRB jettison have been measured in previous missions and are indicated below. The intertank door is located between the -Z and -Y axes, and maximum sound pressure levels outside the IDP are 17.5 dB.

Intertank Location Overall Sound Pressure Level. (dB)

Internal 146.5
External (-Z axis) 153.5
External (+Z axis) 161.5
External (-Y and +Y axes) 175.0

5.5 Acceleration

Maximum design longitudinal (X-axis) acceleration during launch is 3 g. During re-entry, the External Tank reach a maximum acceleration of approximately minus 10 E altitude of 170,000 feet (Fig. 11).

5.6 Payload Design Safety and Proof Factors

For structurally well defined inter-tank hardware, the safety factors for ultimate and yield conditions, as well as proof factors for fracture and non-fracture controlled conditions under well defined static and/or pressure loading conditions, are shown below. Safety Factors Proof Factors Component Ultimate Yield Fracture Non-Fracture Inter-tank 1.25 1.10 1.05 1.05


ETCO will perform both analytical and hands-on payload integration. Analytical integration will combine payloads into missions which make most efficient use of the resources provided by the IDP and HIDP while assuring no payload interferences. This analysis also allocates available sources among users, establishes functional interfaces between payload elements and IDP/HIDP supporting systems, establishes requirements on distributing systems, and produces structural, safety, test and operational analyses or plans. Hands-on integration provides the design and fabrication of mission peculiar systems, performs the actual build-up of the integrated pallets and carries out the testing and checkout of the completed pallets. Users will be involved in most of these activities. Figure 10: Intertank Compartment Pressure During Ascent (see pdf for actual graph) Figure 11: ET Acceleration during Re-entry (see pdf for actual graph) Appendix A: Acronyms and Abbreviations

DOD Department of Defense
ET External Tank
ETCO External Tanks Corporation
HIDP Heavy Inter-tank Door Pallet
IDP Intertank Door Pallet
KSC Kennedy Space Center
LEO Low Earth Orbit
MECO Main Engine Cut Off
NSTS National Space Transportation System
RF Radio Frequency
RFP Request for Proposals
ROM Rough Order of Magnitude
RSS Range Safety System
SRB Solid Rocket Booster
TBD To Be Determined
TPS Thermal Protection System
UCAR University Corporation for Atmospheric Research

Appendix B: IDP & HIDP Launch Services Request

Organization: Date:
Vehicle (check one): __ IDP __ HIDP __ Ejection from HIDP

TECHNICAL (attach additional sheets as needed)
Mission: Inclination degrees; Maximum Altitude km
Launch Window from to
Recovery of Payload: __ Yes __ No
Recovery of Data Capsule: __ Yes __ No
Ejection into Suborbital
Ejection and Boost to Orbit
Operational Mass: Total kg; Ejected Payload Mass: hz
Payload Dimensions (provide drawings): Height cm; Width Depth cm; cm
Protrusions (describe)
Payload Handling:
Special Safety Requirements:
Special Manifest Requirements:
Other Requirements:
UCAR Member Institutions
University of Alaska
University of Arizona
California Institute of Technology
University of California at Davis
University of California at Irvine
University of California at Los Angeles
University of Chicago
Cornell University
University of Denver
Drexel University
Florida State University
Georgia Institute of Technology
Harvard University
University of Hawaii
University of Illinois at Urbana – Champaign
Iowa State University
Johns Hopkins University
University of Maryland
McGill University
University of Miami
University of Michigan
University of Missouri
Naval Postgraduate School
University of Nebraska at Lincoln
University of Nevada
New Mexico Institute of Mining and Technology
State University of New York at Albany
New York University
North Carolina State University
Ohio State University
University of Oklahoma
Old Dominion University
Oregon State University
Pennsylvania State University
Princeton University
University of Rhode Island
Rice University
Saint Louis University
Scripps Institute of Oceanography
Stanford University
Texas A&M University
University of Texas
Purdue University
University of Toronto
Utah State University
University of Utah
University of Virginia
Washington State University
University of Washington
University of Wisconsin at Milwaukee
Woods Hole Oceanographic Institution
University of Wyoming
Yale University

1877 Broadway
Boulder, CO 80302
Telephone: 303-444-6221
FAX: 303-444-7047
University Corporation for
Atmospheric Research

View original Intertank Door Pallets Users Guide, May 5, 1989 (pdf)

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