Observations of the performance of the U.S. Laboratory 

Architecture

 

Rod Jones 

National Aeronautics and Space Administration, Lyndon B. Johnson Space Center 

.

ABSTRACT 

The United States Laboratory Module “Destiny” was 
the product of many architectural, technology, 
manufacturing, schedule and cost constraints 
which spanned 15 years. Requirements for the 
Space Station pressurized elements were 
developed and baselined in the mid to late ‘80’s. 
Although the station program went through several 
design changes the fundamental requirements that 
drove the architecture did not change. 
Manufacturing of the U.S. Laboratory began in the 
early 90’s. Final assembly and checkout testing 
completed in December of 2000. Destiny was 
launched, mated to the International Space Station 
and successfully activated on the STS-98 mission 
in February of 2001. The purpose of this paper is to 
identify key requirements, which directly or indirectly 
established the architecture of the U.S. Laboratory. 
Provide an overview of how that architecture 
affected the manufacture, assembly, test, and 
activation of the module on-orbit. And finally, through 
observations made during the last year of operation, 
provide considerations in the development of future 
requirements and mission integration controls for 
space habitats. 

ARCHITECTURE AND REQUIREMENTS 

In normal building construction the product of 
“architecture” are the drawings and specifications, 
which identify hardware requirements and depict 
the integrated design. In the Space Station program 
the “architecture” was established through the 
specification of key hardware features and 
constraints. These features imparted an inherent 
capability that was used to help manufacture, 
assemble, test and activate the hardware.  

The original requirements were established early in 
the development phase of the Space Station 
program. SAE paper “ Early Decisions for Space 

Station “ 2000-01-2329 described the requirements 
selection process used to define the quadrant or 
four post architecture of the Space Station 
pressurized elements. The key features where the 
pressure vessel envelope, standoffs, racks and 
hatch shape and size. 

 

 

 

Don Magargee demonstrating the 1985 

McDonnell Douglas proposed quadrant design

 

AIAA Space Architecture Symposium

10-11 October 2002, Houston, Texas

AIAA 2002-6100

Copyright © 2002 by the American Institute of Aeronautics and Astronautics, Inc. No copyright is asserted in the United States under Title 17, U.S. Code.
The U.S. Government has a royalty-free license to exercise all rights under the copyright claimed herein for Governmental purposes.
All other rights are reserved by the copyright owner.

 

NASA 1985 Crew Station Review No.2 sketch 

depicting key architectural features for the four 

standoff concept 

 

 

Early model depicting standoff and rack 

architecture and depicting rack rotation

 

Module:

 The size of the modules was dictated by 

the cargo bay capacity of the Space Shuttle. As 
defined by the International Space Station Interface 
Definition Document NSTS-21000-IDD-ISS, the 
maximum dynamic envelope diameter of the 
module is 180 inches. Once the primary structure 
was completed it was installed in the element 
rotation stand. It was supported through the launch 
longerons and trunions that were eventually used to 
secure the module in the cargo bay for launch. This 
stand allowed the module to be rotated 360 
degrees. Rotating the module facilitated access to 
the external and internal surfaces during assembly. 

 

 

External view of the Destiny module installed in 

the Element Rotation Stand prior to installation 

of multi layer insulation and meteor debris 

shields 

Standoffs:

 The standoffs were defined as the 

areas for structure to support the distribution of 
utilities, attach core hardware such as lights and 
vents, and to provide on-orbit attachment points for 
racks. In order to allow the various teams of 
technicians to work simultaneously they were 
assembled outside of the module. 

 

 

Destiny module standoff during assembly

 

Each standoff was a self-contained element. This 
allowed power and fiber optic harnesses, hoses 
and vacuum lines to be tested and verified while 
there was adequate accessibility. Once assembly 
and testing was complete the  standoffs were 
inserted into the module, suspended from a rail that 

passed through both ends of the module, and 
lowered into place 

 

 

Destiny standoffs (foreground) and module 

(background) during early assembly

 

 

Installation of the first standoff into the module

 

Endcone area:

 The endcones of the module 

provide a zone for the subsystem distribution lines 
and cables to transition from the standoffs to the 
hatch to feed though to the next module. The use of 
the endcone areas was not specified. Although the 
requirements required system designers to 
package hardware into the racks the endcone’s 
afforded valuable outfitting space that could not be 
wasted. Consequently several major subsystem 

components were located in this area including data 
management mass memory units, power system 
controllers, and emergency response equipment 
including portable fire extinguishers and portable 
breathing masks. All hardware layouts had to 
conform to the same accessibility requirements for 
maintenance and change out. Unlike the standoffs 
and racks the endcone’s had to be outfitted inside 
the module therefore assembly and test of this area 
was in the critical path to completing the module.

 

 

Endcone outfitting prior to closeout installation 

 

Endcone with closeouts in place 

Racks:

 Racks were defined as the primary method 

of hardware system and payload packaging for on-
orbit change out. Similar to the standoffs this 
allowed for the independent assembly and checkout 
of each rack prior to installation in the module. This 
enabled a significant portion of the sub systems be 
integrated in parallel. 

Rack level packaging allowed the program to 
respond to significant requirements changes 
without having to redesign the entire module. In the 
Freedom program the baseline requirement was to 
orbit the space station at a low inclination. When 
Russia joined the ISS program the stations 
inclination was raised to 51.6 degrees. This 
inclination significantly reduced the amount of cargo 
the Shuttle can carry on any one mission. The Lab 
manufacturer was able to minimize the impact from 
this change by off loading non-essential racks. The 
off loaded racks were carried to orbit on subsequent 
missions in the Multi Purpose Logistics Module 
(MPLM). 

 

 

 

 

Equipment Rack during assembly 

  

Payload EXPRESS Rack during standalone 

checkout testing 

Racks were installed and removed numerous times 
during the test phase of the program in order to 
resolve anomalies or replace failed components.

 

 

Rack being installed in the module

 

Hatches:

 The hatch was sized to accommodate 

the on-orbit transfer of racks, cargo and crew. 
Special ground handling equipment is required to 

pass racks through the hatch and install them on 
the ground. Due to the tight tolerances between the 
hatch and the rack a dolly and track system is used 
to pass the rack through the hatch for module 
outfitting. The Multi Purpose Logistic Module 
(MPLM) employees a large aft access hatch which 
in only operable on the ground. The large opening 
provides greater clearance between the rack and 
the hatch and allows the use of specialized boom 
crane named the Rack Insertion Device.  

 

 

MPLM Aft Access Closure 

Stowage:

 The original primary resupply and orbit 

stowage unit was the Resupply Stowage Rack 
(RSR). This was a hard walled locker system 
where each locker is designed to protect its 
contents from the rest of the cargo in the rack. 
Although cargo friendly the weight of the rack is 
close its cargo carrying capability.  

 

Resupply Stowage Rack attached to ground 

support equipment 

 

Stowage Locker 

In order to save weight and to provide additional 
stowage on-orbit the program developed a Zero-g 
Stowage Rack (ZSR). This fabric rack could be 
launched in the empty rack bays in the module and 
deployed to hold cargo on-orbit.

 

 

ZSR installed in the Unity Node 

Resupply Stowage Platform (RSP) was developed 
with the desire to reduce the weight of the structure 
there by allowing more mass to be allocated to the 
cargo. The RSP consists of a center plate with 
attach point allowing bagged cargo to be strapped 
to both sides. Although the rack weight is 
significantly reduced the bags provide less cargo 
protection than the RSR lockers so more padding is 
required reducing the volumetric efficiency. Each 
resupply mission is made up of a complement of 
RSR’s and RSP’s depending on the cargo 
requirements.

  

 

Interior of Multi Purpose Logistics Module on-

orbit 

 

Resupply Stowage Platform 

 

Resupply Stowage Platform packed for a 

mission

 

STS-98 Launch Package 5A Mission:

 The 5A 

mission launched in February of 2001 and ended 
with the successfully installation and activation of 
the destiny module. The mission went according 
the plan outlined in SAE paper “

Architecture in Mission 

Integration, Choreographing Constraints”

 2000-01. 

 

 

 

STS-98 with the Destiny module during 

approach to ISS 

 

Destiny module being removed from the cargo 

bay 

The Destiny module was launched with 5 system 
racks, 8 ZSR’s, a minimum number of crew 
restraints and 10 rack front closeout panels. The 
closeout panels were fabric rack front partitions 
required to maintain proper aisle airflow 

Destiny interior after on-orbit activation during 

ingress by the crew 

After the module was berthed to the ISS the crew’s 
primary task was the set up and activation of the 
Lab systems.  

 

Initial Lab outfitting

 

One key task was the relocation of the Atmosphere 
Revitalization System rack. It was launched in a 
location that optimized the center of gravity for the 
module for launch. This required the crew to 
relocate it on-orbit prior to activation. Although 
mock-ups depicting various portions of the task had 
been used to demonstrate the concept it was not 
possible to simulate end-to-end task. 

 

 

 

Early mockup demonstration of rack installation 

The crew demonstrated on 5A and subsequent 
outfitting missions have shown that rack  transfer 
and installation is a relative easy job for the crew to 
perform and does not require the use of specialized 
handling aids. 

 

Crewmembers performing the first on-orbit 

rack relocation 

 

 

Rack tilted out for standoff maintenance 

 

Lab interior during Expedition 

 

Deployment of a vacuum hose 

 

 

 

Robotics Workstation 

 

Adapting the environment to meet real life 
needs:

 The crew has made numerous on-orbit 

additions and modification to the environment to suit 
their particular needs. The following images depict 
some of those changes.

 

When the Service Module was launched the table 
was offloaded because of limited ascent 
performance. The crew improvised a table from 
excess flight support equipment. 

 

 

Installation of “Shep’s Table” 

 

 

“Shep’s” table in use 

The crew added a ships bell to announce and 
arrival of a new crew to the Station and a ships log 
to document their visit. 

 

Ships bell 

 

Visiting crews leaving their patch 

 

Ships Log

 

The initial requirements specified that the Russian 
partners would provide three crew quarters. The 
Service Module was designed for only two crew. 
The two program agencies could not come to 
agreement on the adequate implementation of a 
third crew quarter on the Russian Segment. The 
Temporary Sleep Station (TeSS) was developed 

and installed in the Destiny module. It has many of 
the key features envisioned for the US habitation 
module crew quarters including a bump out to 
provide adequate internal volume, wall mounted 
sleep restraint, a workstation, and surface to put up 
personal mementos. 

 

 

 

Mock ups of the Habitation module crew 

quarter concept 

 

TeSS deployed in the Destiny module 

 

TeSS interior 

 

Mock up of improvised use of aisle for sleeping 

 

 

Mock-ups were used to demonstrate the impact. Of 
sleeping in the aisle when the program began 
evaluating the delay of the U.S. Habitation module 
crew quarters. The program did not address the 
accommodations of visiting crew which have used 
the Lab module as their make shift crew quarters. 

 

 

 

 

Crew sleeping in the Lab 

 

Interior mockup, the way the designers 

envisioned it 

 

STS-98 and Expedition 1 crew in Unity Node, 

note the significant amount of non standard 

stowage 

 

Visiting Crew in Unity Node, note stowage in 

radial port  

The way the crew really lives

 

 

View of ISS with the Destiny module attached 

taken during STS-98 fly around

 

 

 

CONCLUSION 

The US Segment of the ISS has benefited from the 
establishment and adherence to key fundamental 
architectural requirements. The architectural 
requirements adequately addressed hardware 
change out, modularity and maintainability. These 
features will hopefully ensure the maintenance, 
operability of the hardware, and safe occupation of 
the Space Station for the next 20 plus years.  

That  said the aisle, the habitable volume, has not 
been protected or managed well. ISS operations are 
demonstrating that the original set of requirements 
and constraints on the vehicle’s architecture are not 
adequate on their own to manage the on going 
changing environment. We failed to predict the 
impact and adequately provide the internal 
architectural features required to allow the crew to 
modify the environment for their day-to-day needs. 

We failed to establish the controls to manage the 
addition of new hardware requirements including 
temporary cabling, networks, payload design 
worksite set up and operations, and the impacts 
from visiting crew. Development of a full 
complement of planning and operations constraints 
and tools to track and manage the interior remains 
a work in progress as we gain more experience 
with living and working in the vehicle’s defined 
architecture.  The Space Station and future space 
programs will need to define the architectural and 
operational requirements

 

and features to provide 

the designers, operators and inhabitants with these 
controls and tools. 

REFERNECES 

All images courtesy of NASA Digital Imagery 
Management System and photo library. 

Space Station Interface Definition Document NSTS-
21000-IDD-ISS, (current revision) National 
Aeronautics and Space Administration, Lyndon B. 
Johnson Space Center, Houston, Texas, 

ACKNOWLEDGMENTS 

 

Don Magargee and the long list of individuals with 
design and human engineering expertise for their 
contributions to requirements, concepts and ideas 
that helped shape the current architecture of the 
ISS. David Fitts for his review and comments that 
helped improve the message of this writer. 

CONTACT INFORMATION 

Rod Jones, Deputy Manger of the International 
Space Station Mission Integration and Operations 
Mail Code OC, Johnson Space Center, Houston TX. 
77058  

William.r.jones1@jsc.nasa.gov

 

281-244-7941 

 

DEFINITIONS, ACRONYMS AND 

ABREVIATIONS 

ISS: International Space Station 

MPLM: Multi Purpose Logistics Module is used as 
the primary pressurized cargo carrier for the US 
Segment 

RSR: Resupply Stowage Rack 

RSP: Resupply Stowage Platform 

STS: Space Transportation System 

TeSS: Temporary Sleep Station 

ZSR: Zero-g Stowage Rack