Fighter/EW/Helo/Patrol Arc Fault Circuit Breaker Development April 2007 Sue Waggoner Naval Surface Warfare Center Crane (812) 854-4103 4103 susan.waggoner@navy.mil 1
What is the Arcing Fault Problem
Problem Description Thermal Circuit Breakers are not designed to detect arcing (sputtering) faults for aircraft to prevent electrical fires. Arcing faults are the predominate typed of fault on aircraft wiring and do lead to many maintenance actions and possibly fires such as Swissair 111. The FAA reports an average of 3 smoke in the aircraft events/day in the civilian aircraft fleet
Navy Problem Definition NALDA average annual incident rate of 127.4 per aircraft type, 38 types of aircraft corresponds to an incident rate of 4841 per year. Naval Safety Center documented 30 In-flight Navy aircraft wiring fires which caused mission aborts. Existing thermal circuit breakers are not designed to detect arcing faults
Expected Payoffs AFCB protects/provides maintenance information on power wires (15-20% of system wiring) 1 to 2 million organizational man-hours per year are spent troubleshooting and repairing aircraft wiring. With respect to power wiring incidents, AFCB technology will reduce maintenance man-hours by 35% (70,000 hours) reduce mission aborts and NMC hours by 35% ($9M/year) AFCB will protect A/C wiring power system by detecting and isolating arcing fault which can cause smoke in the cockpit mission aborts and fires reduce in-flight electrical fires and subsequent loss of aircraft by 80% ($27.3M/year) Estimated savings of $37.5M per year after full implementation.
What Does An Arc Fault Current Waveform Look Like?
Fixed Wing AC Generator Dry Arc 300 250 200 150 100 Condition F-18 AC 10 AWG 25 Amp (A) MIN Voltage, V 50 0-50 -100-150 -200-250 -300 3.360 3.365 3.370 3.375 3.380 3.385 3.390 3.395 3.400 3.405 Res: 6.667mV, 10µs Time, s 2:28:52 PM, 30 Jul 2002 c:\documents and settings\michael.t.allen\my documents\programs\afcb ground tests 2003\f18 afcb mar2003\ f18 ac 10 awg 25 amp 01.wft 600 F-18 AC 10 AWG 25 Amp (A) MIN 400 200 Current, A 0-200 -400-600 3.360 3.365 3.370 3.375 3.380 3.385 3.390 3.395 3.400 3.405 Res: 33.33mA, 10µs Time, s 2:28:52 PM, 30 Jul 2002 c:\documents and settings\michael.t.allen\my documents\programs\afcb ground tests 2003\f18 afcb mar2003\ f18 ac 10 awg 25 amp 04.wft
Fixed Wing AC Generator Wet Arc 200 Condition F-18 AC 10 AWG 25 Amp (1) MIN, Drip Test 150 100 Voltage, V 50 0-50 -100-150 -200 9.6 9.8 10.0 10.2 10.4 10.6 10.8 11.0 11.2 11.4 Res: 16.67mV, 10µs Time, s 9:58:43 AM, 1 Nov 2002 c:\documents and settings\michael.t.allen\my documents\programs\afcb ground tests 2003\f18 afcb mar2003\ f18 ac 10 awg 25 amp drip 01.wft 800 F-18 AC 10 AWG 25 Amp (1) MIN, Drip Test 600 400 Current, A 200 0-200 -400-600 9.6 9.8 10.0 10.2 10.4 10.6 10.8 11.0 11.2 11.4 Res: 33.33mA, 10µs Time, s 9:58:43 AM, 1 Nov 2002 c:\documents and settings\michael.t.allen\my documents\programs\afcb ground tests 2003\f18 afcb mar2003\ f18 ac 10 awg 25 amp drip 04.wft
Helo AC Generator Dry Arc Condition 250 H6 0 AFCB GEN 6 6 (V an) 200 150 86 Vrms 100 Voltage, V 50 0-50 -100-150 -200-250 3.38 3.40 3.42 3.44 3.46 3.48 3.50 3.52 3.54 3.56 3.58 Res: 8.333mV, 10µs Time, s 2:32:37 PM, 27 Aug 2003 c:\windows\desktop\michael allen\programs\h60 afcb gen aug2003\h60 afcb gen wft files cd1\h60 afcb gen66 _01.wft 800 H6 0 AFCB GEN 6 6 (Ia) Current, A 600 400 200 0-200 244 Amps RMS Current 77 msec -400-600 -800 3.38 3.40 3.42 3.44 3.46 3.48 3.50 3.52 3.54 3.56 3.58 Res: 33.33mA, 10µs Time, s 2:32:37 PM, 27 Aug 2003 c:\windows\desktop\michael allen\programs\h60 afcb gen aug2003\h60 afcb gen wft files cd1\h60 afcb gen66 _04.wft
Helo AC Generator Wet Arc Condition 250 200 150 100 H6 0 AFCB GEN 1 35 (V an) 52.3 Vrms Voltage, V 50 0-50 -100-150 -200-250 7.76 7.77 7.78 7.79 7.80 7.81 7.82 7.83 7.84 7.85 7.86 7.87 Res: 8.333mV, 10µs Time, s 1:14:20 PM, 8 Sep 2003 c:\windows\desktop\michael allen\programs\h60 afcb gen aug2003\h60 afcb gen wft files cd3\h60 afcb gen135 _01.wft 600 400 200 H6 0 AFCB GEN 1 35 (Ia) 258 Amps RMS Current 25 msec Current, A 0-200 -400-600 7.76 7.77 7.78 7.79 7.80 7.81 7.82 7.83 7.84 7.85 7.86 7.87 Res: 16.67mA, 10µs Time, s 1:14:20 PM, 8 Sep 2003 c:\windows\desktop\michael allen\programs\h60 afcb gen aug2003\h60 afcb gen wft files cd3\h60 afcb gen135 _04.wft
Helo AC Generator w/ 200 Amp T/R Dry Arc DC Condition H60 AFCB GEN 180 (V dc) 31 30 28.24 Vdc Mean 29 Voltage, V 28 27 26 25 24 23 2.5 2.6 2.7 2.8 2.9 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 Res: 1.667mV, 10µs Tim e, s 10:39:30 AM, 23 Sep 2003 c:\windows\desktop\michael allen\programs\h60 afcb gen aug2003\h60 afcb gen wft files cd4\h60 afcb gen180 _08.wft 220 200 180 160 140 H60 A FCB GEN 180 (I dc Positive) 50.07 Amps Mean Current, A 120 100 80 60 40 20 0-2 0 2.5 2.6 2.7 2.8 2.9 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 Res: 29.17mA, 10µs Time, s 10:39:30 AM, 23 Sep 2003 c:\windows\desktop\michael allen\programs\h60 afcb gen aug2003\h60 afcb gen wft files cd4\h60 afcb gen180 _09.wft
What Is Being Developed And Tested?
Fiscal Year Arc Fault Circuit Breaker Developmental Timeline 00 01 02 03 04 05 06 07 08 Transport Aircraft Development Lab Test Flight Install Tests Prod. ONR/FAA/AAIPT Component Impr Program Fighter/Helo/Patrol A/C Begin Devel Lab Test Ground Test Flight Test Prod.
Qualified for Commercial Transportation and Military-Commercial Derivatives Originally trying to get from household circuit breaker to a large MS24571 circuit breaker Industry fitted arc fault circuitry into a MS14105 and MS3320 AFCB - MS14105
AFCB Testing Defining Arcing Waveforms Defining Electrical Load Waveform EMI Testing Temperature Altitude Testing Vibration Testing Electrical Testing Flight Testing
Flight Tests NAVAIR C-9B 500 Flight Hours Six AFCB H-53 25 Flight Hours Six AFCB F/A-18, H-60, P-3 Planned for FY07 FAA Boeing 727 50 Flight Hours 20 AFCB Industry Boeing 767 Quantus 737 10000 Flight Hours
AFCB Transition Plan Transition for legacy aircraft through retro-fit on typical 30 month inspection phase Transition through retrofit or preferred spare part Transition Starts in FY07 depending upon company tooling capability Transition Platforms H-53 P-3C F/A-18 H-60 PMA-261 PMA-290 PMA-265 PMA-299
Project Highlights Arc Faults have been a constant problem for the past 10 years Timeline 6.3 development in FY02 ready for transition to E&MD in FY07 AFCB selected as part of the Core Program under FNC-TOC (6.3 funds) Cooperating with Air Force and FAA investigating the problems of arc faults in aging wiring systems with transition opportunities exist within Navy, other Government agencies, and industry