# Presentation: 104105

**The Cost of Maintaining Thermal Protection Systems**
**	****	****	****	****	****Frank E. Jones**
**	****	****	****   ****	****   ****NASA-KSC**

**July 1999**

## Agenda

**Background**
- Design Overview
- Maintenance Drivers
**Factors Affecting Cost**
- Materials
- Access
- Touch Time Labor
- Costs per TPS Type
- Off Line Support
**Improvements To Reduce Cost**
- Presently In-work
- Future Necessities
**Beyond Shuttle**

## TPS Surfaces

**TPS Surfaces**

- Lower Surface

- Upper Surface

**TPS Legend**

- HRSI (Black) Tiles
- LRSI (White) Tiles
- AFRSI Blankets

- Glass
- Exposed Metallic Surfaces

- FRSI
- RCC

## Tile Configuration

**Tile Configuration**

- Densified IML Surface

- Silicone RTV Adhesive

- SIP

- Filler Bar

- Coating Terminator

- Uncoated Tile

- Koropon-Primed
- Structure

- LRSI Tile White
- Glass Coating

- HRSI Tiles - Black RCG Coating

- Step

- Gap

## Fibrous Insulation Blankets

**Fibrous Insulation Blankets**

- RTV Transfer Coated
- Surface on IML

- A

- A

- Quartz
- OML
- Thread

- Quartz
- OML Fabric

- D

- D

- C

- C

_**View C-C**_

_**Section A-A**_

_**View B-B**_

- OML Fabric
- Folded Over
- To IML and
- Stitched
- Through
- Thickness

- B

- B

- Quartz Batting

- Glass IML
-  Fabric

- Glass IML
- Thread

- IML Fabric

- OML Thread

- Batting

- OML Thread

- IML Thread

- OML
- Thread

- IML
- Thread

_**Detail E**_

_**Section D-D**_

- E

- OML
- Fabric

- IML
- fabric

- OML
- Thread

## Leading Edge RCC

**Leading Edge RCC**

- Upper
- Left
- Wing

_**Section C-C**_

- C

- C

_**Detail D**_

- D

_**Section E-E**_

- Lower Wing  HRSI Tile

_**Section B-B**_

_**Section A-A**_

- B

- B

- E

- Upper Wing AFRSI

- Wing Spar

- Thermal Barrier

- Interface Gap
- Between
- RCC and
- HRSI Tiles

- A

- A

- E

- Fixed Upstream  Gap Between
- Panel and Tee Seal

- Variable Downstream Gap
- Between Panel and Tee
- Seal For Thermal Expansion
- Allowance

- I nconel
- Attachments

- ACSS Hardware

- RCC Panel
- (In Foreground)

- RCC
- Tee Seal Web
- (In Background)

- HRSI Tiles

- Upper LESS
- Access Panel
- HRSI Tiles

- Horsecollar
- Peripheral Gap Filler

- Lower LESS Access
- Panel HRSI Tile

- Upper Wing

- I nconel
- Insulators

## Gap Fillers

**Gap Fillers**

_**Pillow With Sleeving**_

_**Pillow  Captive Type**_
_**(Single Lip)**_

_**Ames Type**_

- RTV or Ceramic Coated  Nextel Fabric

_**Pillow Captive Type**_
_**(Double Lip)**_

- Nextel Ceramic
- Fabric

- Saffil Alumina Batting

- Inconel Foil

- Nextel Ceramic Fabric

- Nextel Ceramic Sleeving

- Saffil Alumina
- Batting

- Inconel Foil

_**Pillow or Pad Type**_

- Nextel Ceramic Fabric

- Saffil Alumina Batting

- Inconel Foil

- Saffil Alumina
- Batting

- Inconel Foil

- Nextel Sleeving

- Nextel Ceramic Fabric

## Thermal Barrier & Seal Locations

## Typical Thermal Barrier

**Typical Thermal Barrier**

- RTV-Stiffened Fabric Tail

- Inconel Spring Tube

- Nextel Sleeving

- Nextel Fabric

- Thermal Barrier Support

- Thermal Barrier Carrier Plate

- Main landing Gear Door Side Tile

- Thermal Barrier

- Structure Side Tile

_**Typical Thermal Barrier Detail**_

_**Main Landing Gear Door Thermal Barrier**_

## Elevon Cove Seal

- Lower Elevon
- TPS

- Spanwise Polyimide
- Primary Seal

- 0.5”
- Gap

- HRSI
- Tiles

- Pillow Gap Filler

- Lower Wing TPS

- Upper Wing TPS

- Flipper
- Door

- Flipper Door Seal

- Elevon Rub Panel

- Elevon Rub Tube

- Hinge
- Pins

- Uncoated AFRSI
- Blankets

## Orbiter TPS

- Average tiles damaged from  flight requiring replacement     	          ~20
- Average tiles replaced per flow			          ~75
- HRSI tiles on the Orbiter				          ~19,700 (9 lb), 525 (22 lb)
-  TUFI tiles on the Orbiter				            306 (8 lb)
- FRCI tiles on the Orbiter				            2,950 (12 lb)
- LRSI tiles on the Orbiter				            725 (9 lb), 77 (12 lb)
- FIB blanket area on the Orbiter			            2,123 sq ft
- FRSI sheet area on the Orbiter			            2,024 sq ft

## Flight Damage History

## Materials Cost

**Raw Materials*****	****	****$200k / Flight**
**Tile PU’s****	****	****	****$137k / Flight**
**Consumables****	****	**** $ 10k / Flight**
**Total  ****	****	****	****	****$347k / Flight**

******* ****TPSF = RTV’S, Threads, Fabrics, Coatings, etc. **

## Work Access

## Causes for R&R

- Flight
- 33.80%

- Modification
- 32.39%

- Out-of-Tolerance
- 6.34%

- Ground  Handling
- 5.63%

- Access
- 21.83%

## TPS Discrepancies

**TPS Discrepancies**

- RSI Tiles
- 73.75%

- FRSI, Filler Bar,
- and All Others
- 3.56%

- Gap Fillers,
- Thermal Barriers,
- and O/T Conditions
- 16.30%

- FI Blankets 3.50%

- Re Water
- Proofing
- 2.88%

## Work Load for Component R&R

**Work Load for Component R&R**

- Simple NC
- Tile
- 35.02%

- Complex Splash
- Tile 7.79%

- FRSI 0.20%

- Complex NC
- 25.29%

- Simple AFRSI 3.85%

- Complex AFRSI 0.72%

- Tile Reinstallation 4.18%

- Simple Splash
- Tile
- 22.96%

## Labor Hours per Type

## Tech Labor Breakdown

**Tech Labor Breakdown**

- Removals &
- Replacements
- 55.70%

- ML0601-9025
- Repairs
- 12.03%

- ML0601
- Repairs
- 10.71%

- MDR Repairs
- 14.27%

- ML0601-9024 Rework 4.41%

- Re water Proofing  2.88%

## Labor Touch Time per TPS Type

**  ****Tile          =  2.27 hours/sq.ft.**
**  ****FIB          =  0.16 hours/sq.ft.**
**  ****FRSI        =  0.02 hours/sq.ft. **
**  ****ET SOFI   = 0.70 hours/sq.ft.**
**	****	**

## Discipline Comparison

- Maintenance
- Technicians
- 37%

- Logistics 3%

- Operations 8%

- Quality Assurance
- 15%

- Engineering
- 18%

- Manufacturing
- Technicians
- 19%

## Orbiter Processing at KSC

## OPF Processing

**OPF Processing**

- Orbiter Landing at KSC, Tow to OPF, Jack and Level

- PLBD Strong back Installation, PLBD Open Up

- TPS Post Flight Inspection

- TPS Waterproofing

- TPS Processing

- Payload Removal

- Payload Bay Reconfiguration

- FRCS Functional

- SSME Heat Shield Removal

- SSME Removal

- OMS Pod Functional

- Hydraulic System Fill and Bleed Removal Aerosurfaces

- Fuel Cell Voltage Test

- Payload Premate Testing

- Drag Chute Installation

- APU Servicing and Checkout

- Payload Bay Cleaning

- Payload Installation

- SSME Installation

- All Closeouts

- Final Payload Bay Cleaning

- ET Door Functional

- SSME Heat Shield Installation

- MPS/ SSME Integration

- TPS Rollout Inspection

- Landing Gear Door Functional

- PLBD Closure

- Orbiter Jack Down, WT & cg, OTV OPS

- Orbiter Power Down

- Roll Out VAB

- 1 Week

- TPS Operations

- SSME/MPS Ops

- Payload Ops

- Vehicle Ops

## TPS Workforce

## Past TPS Organization

## Present TPS  Organization

## Improvements To Reduce Cost

**	****Presently In-work**
**Processing Reductions**
**Less Toxic Re-Waterproofing**
**Surface Defect Analyzer**
**	****Future Improvements**
**White TUFI**
**Ceramic Captive G/F**
**Thermal Barrier Improvements**

## Beyond Shuttle

**  ****Internal Vehicle Health Monitoring**
**  ****RF replaces Ground Connections**
**  ****No Penetrations**
**  ****No Windows**
**  ****Self Healing TPS**