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Demistifying Service Life ASNE Flagship 18 Jan 2011 Chris Cable Director, Auxiliary and Special Mission Ship Design Division (SEA05D4) Naval Sea Systems.

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Presentation on theme: "Demistifying Service Life ASNE Flagship 18 Jan 2011 Chris Cable Director, Auxiliary and Special Mission Ship Design Division (SEA05D4) Naval Sea Systems."— Presentation transcript:

1 Demistifying Service Life ASNE Flagship 18 Jan 2011 Chris Cable Director, Auxiliary and Special Mission Ship Design Division (SEA05D4) Naval Sea Systems Command Christopher.w.cable@navy.mil (202) 781-1943

2 Tell them what you are going to tell them Tell them Terminology Why an understanding of Service Life is important Current ESLs by class Data on ASLs Why do ships get retired before their ESL? So what?? NEEC = Naval Engineering Education Consortium Tell them what you told them! SERVICE LIFE – Outline 2

3 Tell them what you are going to tell them: 1. An understanding of Service Life is important to all Naval Engineers. 2. Service Life Terminology is often misunderstood. 3. Expected Service Lives change over time. 4. Actual Service Lives seldom equal Expected Service Lives. 5. How we Design ships to meet Expected Service Lives needs more attention. 6. A pressing need is to develop innovative ways to get ships to make it to their Expected Service Lives (NEEC might be able to help). SERVICE LIFE – The Story 3

4 Terminology: ESL = Expected Service Life. The number of years ships need to be kept in service to achieve a given force structure. ASL = Actual Service Life. C hronological life from commissioning to decommissioning. CASL = Class Avg. Service Life. Average ASL by class. DSL = Design Service Life. The service life the ship is designed to achieve. SERVICE LIFE REQUIREMENT. ICD, CDD, COR, SPEC, etc. MID-LIFE = Mid life upgrades to get To ESL. SLEP = Service Life Extension Program. Major upgrades to get BEYOND the ESL. 30 YSP = 30 Year Shipbuilding Plan. The Navy tool for projecting force structure. RECAP = Recapitalization. Buying new ships to replace retiring ships and/or to maintain the desired force structure. SERVICE LIFE – The Basics Ref: Ship Service Life and Naval Force Structure, P. Koenig, D. Nalchajian and J. Hootman, ASNE symposium, Engineering the Total Ship 23-25 Sep 2008 4

5 Things you do “in utero” to ensure a healthy start to life and room to grow (need more!!). THE BASICS - An Irreverent Look The Basics: Chronological View ESL 30 Year Shipbuilding Plan D&C Margins SLA DSL Mid-Life SLEP Recapitalization ASL CASL Only death and taxes are certain. These can change during any period of your lifespan. Normal life expectancy. Think of a “lifespan” Dad, take your Lipitor! Time for a quadruple bypass…… …while Mom thinks about your replacement? How long did you live? How long did you family live on average? 5

6 It is the foundation of the shipbuilding plan, the basis for recapitalization Excerpts from the CNO’s Guidance for 2011 (Oct 2010): (emphasis added) “Continue to be the most dominant, ready and influential naval; force, globally and across all naval missions.” “…conducting essential maintenance and modernization to ensure units reach full service life…” “Build a Navy with appropriate force structure and strategic laydown necessary to implement the Maritime Strategy.” “We must maintain the Fleet we have to the end of its expected service life…” SERVICE LIFE – Why Important? 6

7 Current ESLs by class: SERVICE LIFE – ESLs by Class Ship Class ESL 1986 ESL 1990 ESL 1992 ESL 1995 Prop ESL 1998 ESL 2006 ESL 2007 ESL used in Yr Plan CVN 68 45 50 FFG 73035 20-2530 PC15 CG 47 40 25 n/VLS 35 VLS 35 DD 9633040 20n/VLS 30-35 VLS 35 DDG 513040 35 40 DDG 1000 35 7

8 Current ESLs by class: SERVICE LIFE – ESLs by Class Ship Class ESL 1986 ESL 1990 ESL 1992 ESL 1995 Prop ESL 1998 ESL 2006 ESL 2007 ESL used in Yr Plan LCS 25 LPD 17 40 LSD 41/49 3540 LHA 135 4035 LHD 13540 T-AO35 T-AKE 40 8

9 Current ESLs by class: SERVICE LIFE – ESLs by Class Ship Class ESL 1986 ESL 1990 ESL 1992 ESL 1995 Prop ESL 1998 ESL 2006 ESL 2007 ESL used in Yr Plan MCM30 MHC 30 strike MPF(F) MLP 40 T-ATF35 40 JHSV 20 9

10 Why do ESL change over time? Many factors: Force Structure evolving (build up) Force Structure evolving (build down) Stroke of the pen Balance the plan Engineering insight (but not enough of the time!) SERVICE LIFE – Why ESLs change over time 10

11 Data on ASLs SERVICE LIFE – CASL info Class CASLLatest or Current ESL FFG121.335 FF105221.135 DD96323.635 FFG7 Flt 1&218.430 CG47 blk 119.635 CV6340.445 CV6738.645 CVN6550 y ESL55 LPD133.235 LPD4Some 40+35 LSD3630.535 11

12 12 SERVICE LIFE - Does ASL correlate to displacement? Answer = Yes

13 13 SERVICE LIFE - Does CASL correlate to Displacement Answer = Yes Note: Includes all decommissioned Cruisers, Destroyers, Frigates, and Patrol Craft built after World War II. Active ships not shown.

14 14 Single mission shipsMulti-mission ships SERVICE LIFE - Does ASL correlate to multi- mission vs. single-mission Answer = Maybe

15 15 SERVICE LIFE - “Birth date” matters because of external events

16 Why do ships get retired before their ESL? Many possible factors: Treaties Stability issues Mission system unable to meet threat Material Condition Damage (grounding, fire, high sea state structural damage, etc) Loss (wartime) Business Case (cheaper to build new??) Industrial Base considerations Environmental Considerations (ex: double hulling) Changes in the nature of the threat (Littorals, BMD, etc) Costs to operate (Fuel Efficiency, Manning costs, etc) Cost to get to ESL are prohibitive Mission goes away SERVICE LIFE – Factors for Early Retirement 16

17 Then as Indonesian DE 342, served 1974-2007+ = 33+ more years as gunboat DE 1035 USN 1958-1974 = only 16 years due to being ineffective against nuclear submarines Same ship, two missions 17

18 1970’s to Early 1990’s GENSPEC was not specific about Design Service Life. Some editions made oblique reference to a presumption that ships generally would be in service for 25 years. Thus the assumption of a 25 year life for surface ships (with no growth or mods occurring in the last five years). Some of our margin policies (e.g., required electric plant service life allowance) have been indexed to that number for many ship classes. With respect to the hull, fatigue life was not a controlling factor. Structures folks assumed their designs had enough margin that, provided you repaired any degradation as it occurred, the hull would last an unlimited duration. SERVICE LIFE – DSL info 18

19 LPD 17 (early 1990s) onward LPD 17 = 1st program where we dealt with DSL meaningfully. Requirement was set for a 40-year ship life. Whole ship FEM models have been built for LPD 17, but in terms of validation to demonstrate that the hull meets the fatigue requirement, the methods used there were simplified in comparison to the process used today. All ships (except JHSV) after LPD 17 had OPNAV-specified ESL requirement. On JHSV they said essentially "I'll let that float in the interests of cost and will take what I get.” Though OPNAV typically uses ESLs as "planning numbers" to guide a range of activities, few people understand that they have no direct basis in engineering for older ships. SERVICE LIFE – DSL info (cont.) 19

20 Service Life Allowances (SLAs) – when delivered each ship shall be capable of accommodating growth during its service life w/o compromise of hull strength, reserve buoyancy and stability characteristics. Anticipated growth consists of authorized changes (like ship alts and mission upgrades) as well as unauthorized changes (like too much paint and extra coke machines). SLA NOT THE SAME AS DESIGN MARGINS SLAs for Weight, KG, Electrical, A/C, Hull Strength, Accommodations, Fatigue Life Notes: As SLA consumed, performance characteristics degrade (speed is at delivery). Major modification / conversions typically account for providing SLA compensation. When SLA fully consumed, may need Weight and Moment Compensation. SERVICE LIFE – Service Life Allowance 20

21 So What? Excerpts from the CNO’s Guidance for 2011 (Oct 2010): (emphasis added) “We will continue to pursue affordable warfighting solutions that emphasize evolutionary vice revolutionary capabilities, common hulls and airframes, open architecture, modularity, lower energy footprint, and reduced manpower.” Design ships to meet their ESLs -- develop the engineering understanding of the technical underpinnings to Design Service Life. SFA Corrosion Allowance / high performance materials. More mission modular – maybe. Business case? Nobody doing it commercially? Open architecture (broadly) – probably. Aircraft Carrier example – you can argue that Carriers have such long lives because the aircraft are the modular mission packages. Innovate with new ways to help existing ships meet their ESLs (Goal: ASL=ESL) SERVICE LIFE – So What? 21

22 22 Modular combat system?? 1945 prop Hellcats 1991 supersonic Hornets USS Midway, 1945-1992, 47 years

23 So What? Excerpt from the CNO’s Guidance for 2011 (Oct 2010): (emphasis added) “We will lead Science, Technology, Engineering, and Math (STEM) education and outreach to grow top technical talent to lead tomorrow’s Navy…” NEEC – Project based education – we need to get SUSTAINMENT projects in front of the students Contact for Project ideas: NEEC Director = Mr. Steve Ceccio (possibly develop the course: what every Naval Engineer Needs to Know About Service Life) Contact for Mentoring : Mr. Bob Keane Innovate with new ways to help existing ships meet their ESLs Predictive Tool. Project Ideas. “What every Naval Engineer needs to know about service life” SERVICE LIFE – So What? (cont’d) 23

24 Tell them what you told them! 1. An understanding of Service Life is important to all Naval Engineers. 2. Service Life Terminology is often misunderstood. 3. Expected Service Lives change over time. 4. Actual Service Lives seldom equal Expected Service Lives. 5. How to Design ships to meet Expected Service Lives needs more attention. 6. A pressing need is to develop innovative ways to get ships to make it to their Expected Service Lives (NEEC might be able to help!). SERVICE LIFE – Summary 24


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