# NTSB NYC08IA290: Boeing 747-209B, N715CK, Bogota, Colombia, August 26, 2008 - Type: NTSB incident investigation - Classification: Incident · No injuries · Incident investigation · Final report - Date: August 26, 2008, 06:35 local (06:35 UTC) - Place: Bogota, Colombia - Coordinates: 4.716388, -74.156387 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=4.7164&lon=-74.1564&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Defining event: [Takeoff: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: No injuries - Injuries: 5 uninjured - Status: Completed, report May 19, 2011 - Report: Approved by Office Director - Parties: Kalitta Air, The Boeing Company, Pratt & Whitney, AAI-100, Accredited Representative - Colombia - NTSB case key (mKey): 68852 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC08IA290 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/68852/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=68852 - Page: https://openairdocs.org/ntsb/NYC08IA290 ## Probable cause The combination of fan blade edge contour, variable blade trim, and the high altitude, which resulted in an engine surge. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Power plant](https://openairdocs.org/ntsb-findings/01057100): Aircraft › Aircraft power plant · Malfunction (probable cause); cases with it: [Boeing 747-209B, 1 case](https://openairdocs.org/ntsb-findings/01057100/cases.md?model=138489B), [All aircraft, 198 cases](https://openairdocs.org/ntsb-findings/01057100/cases.md) - [Temp/humidity/pressure: high density altitude](https://openairdocs.org/ntsb-findings/03031020): Environmental issues › Conditions/weather/phenomena · Effect on operation (probable cause); cases with it: [Boeing 747-209B, 1 case](https://openairdocs.org/ntsb-findings/03031020/cases.md?model=138489B), [All aircraft, 278 cases](https://openairdocs.org/ntsb-findings/03031020/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Takeoff: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Boeing 747-209B, 2 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=138489B), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) ## Analysis Just after takeoff from a high-altitude airport, as the landing gear were being retracted, a “loud bang” emanated from the vicinity of the No. 3 turbofan engine. The exhaust gas temperature rose, followed by three or four lesser bangs, all of which indicated an engine stall/surge. The engine was secured in accordance with the checklist procedure, fuel was dumped, and the airplane returned to the airport without further incident. On-wing test bed testing first established a performance baseline for the engine, which was then tested with newly overhauled fan blades installed, and subsequently tested with a newly overhauled fan case installed in order to assess the effects of changing fan blade geometry and fan blade-to-fan case clearance. Initial testing of the engine did not result in an engine surge or any engine exceedences. An engine vane control trim check revealed that it was within the parameters for most of the engine power range, except for above the 90 percent corrected N2 speed, where it was slightly below the minimum value. Because the results did not significantly impact testing, the engine was not re-trimmed prior to testing the engine with new fan blades and a new fan case. Tests revealed that fan blade contour and shape had a bigger influence on the engine’s surge margin and low pressure compressor (LPC) stability line than the fan blade-to-fan case clearance variations within the range of test conditions. Fan blades that were within the engine manual limits – rounder leading edges with little to no erosion and proper chord length – had improved LPC efficiency and engine stability. The last engine test was conducted with the compressor variable vanes re-trimmed open, and within limits at the high speed range, with the results indicating further improvement in LPC efficiency and stability. While no single variable likely resulted in the engine surge, several variables, including blade edge contour, variable blade trim and high altitude, likely combined to produce the stall/surge. ## Factual narrative On August 26, 2008, about 0635 coordinated universal time (0135 local time), a Boeing 747-209B, N715CK, operated by Kalitta Air as Centurion Air Cargo flight 164, experienced a power loss from the number 3 engine shortly after takeoff. None of the five crewmembers were injured, and there was no damage to the airplane. Night visual meteorological conditions prevailed. The airplane was operating on an instrument flight rules flight plan from Eldorado International Airport (SKBO), Bogota, Colombia, to Miami International Airport (KMIA), Miami, Florida, in accordance with Title 14 Code of Federal Regulations Part 121. Under the provisions of Annex 13 to the Convention on International Civil Aviation, and by mutual agreement, the Colombian Government delegated the incident investigation to the United States. Aeronautica Civil de Colombia designated an accredited representative to the investigation on behalf of the Colombian Government. According to flight crew statements, just after departure, as the landing gear were being retracted, a “loud bang” emanated from the vicinity of the number 3 engine, followed by an excessive exhaust gas temperature (EGT) and “three or four lesser bangs.” The engine was secured “in accordance with the checklist procedure,” fuel was dumped, and the airplane returned to the airport without further incident. A post-flight walk-around inspection of the number 3 engine revealed no visible damage. The airplane was powered by four Pratt and Whitney (P&W) JT9D-7Q engines. The operator reported that the number 3 engine, ESN P702121, had operated 210 hours since overhaul. A Powerplants Group was formed to further examine the engine. According to the Group Chairman's factual report, the number 3 engine was removed from the airplane and shipped to the Kalitta Air engine facility in Oscoda, Michigan for on-wing testing on a Boeing 747-200 test bed. Before engine testing was conducted, the engine was inspected via borescope to determine internal hardware condition and if the engine was capable of being tested safely. Inspection did not reveal any mechanical failures within the engine, or thermal distress in the combustion or turbine sections beyond serviceable limits. Several high pressure compressor blades were found to be nicked or torn beyond engine manual limits and were repaired (blended in-situ) before the engine was run. Fan blade leading edge impressions were also made to evaluate leading edge contour and profile and their impact on engine performance and stability. The engine was tested in accordance with the P&W "Test Number 12" performance evaluation listed in the JT9D-7Q engine maintenance manual to first establish a performance baseline for the engine, and to sequentially test the engine with newly overhauled fan blades installed, then with a newly overhauled fan case installed, in order to assess the effects of changing fan blade geometry and fan blade-to-fan case clearance. Initial baseline testing of the enginerevealed that the engine did not surge, nor were there any engine exceedences. An engine vane control trim check was performed and revealed that it was within the parameters for most of the engine power range, except for above 90 per cent corrected N2 speed, where it was slightly below the minimum value. It was determined that the results did not significantly impact the engine testing, so the engine was not re-trimmed prior to testing the engine with new fan blades and a new fan case. Based on the range of hardware conditions tested, the tests revealed that fan blade contour and shape had a bigger influence on the engine’s surge margin and low pressure compressor (LPC) operating line than the fan blade-to-fan case clearance variations within the range of test conditions. Fan blades that were within the engine manual limits – rounder leading edges with little to no erosion and proper chord length – had improved LPC efficiency and engine stability. The last engine test was conducted with the compressor variable vanes re-trimmed open, and within limits at the high speed range. The results revealed that LPC efficiency and stability further improved above and beyond the improvement from the overhauled fan blades. ## Aircraft - Registration: [N715CK](https://openairdocs.org/deregistered/N715CK-2015-06-08), registration cancelled 2015-06-08, S/N 22447, built 1982 (OpenAirDocs) - Reported make and model: BOEING 747-209B - Registry model: [Boeing 747-209B](https://openairdocs.org/model/boeing-747-209b) (registry code 138489B) (OpenAirDocs) - Registry engine: [Pratt & Whitney JT9D-3A](https://openairdocs.org/engine/pratt-whitney-jt9d-3a) (registry code 52050, turbo-fan) (OpenAirDocs) - Category: Airplane - Serial number: 22447 - Airframe hours: 87617 - Engines: Pratt & Whitney JT9D-7Q 51100 lbs thrust turbo fan; Pratt & Whitney JT9D-7Q 51100 lbs thrust turbo fan; Pratt & Whitney JT9D-7Q 51100 lbs thrust turbo fan; Pratt & Whitney JT9D-7Q 51100 lbs thrust turbo fan - Damage: No damage - Flight: Part 121 - Operator: Kalitta Flying Service Inc, doing business as Kalitta Air - Registered owner: Kalitta Air - Airworthiness certificate: Standard, Transport - Departed: SKBO, Bogota - Destination: KMIA, Miami, FL - Flight plan: IFR - Airport: SKBO, El Dorado International, runway 31L, 12,467 × 148 ft, concrete ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 55; injuries: none; airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1; last flight review September 30, 2008; seat: left; flight hours: 14,147 total, 2,591 in this make and model, 8,895 as pilot in command, 124 in the last 90 days, 65 in the last 30 days - Co-pilot; age 29; injuries: none; commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1; last flight review August 30, 2007; seat: right; flight hours: 2,000 total, 499 in this make and model, 200 as pilot in command, 118 in the last 90 days, 17 in the last 30 days - Flight engineer; injuries: none; seat: center ## Weather - Conditions: Visual (VMC), Night - Wind: 280° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: 7,000 ft broken - Temperature: 52 °F, dew point 52 °F - Altimeter: 30.29 inHg - Observed at: SKBO ## Docket (31 files) The files NTSB released with the investigation on October 29, 2010, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=68852. 8.8 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 567 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40338552&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Kalitta Initial Incident Report (item 2, .PDF, 78 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40338580&FileExtension=.PDF&FileName=Kalitta%20Initial%20Incident%20Report-Redacted.PDF - Additional Crew Comments (item 3, .PDF, 148 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40338584&FileExtension=.PDF&FileName=Additional%20Crew%20Comments-Master.PDF - FDR Data Subset (13 Parameters) (item 4, .PDF, 746 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40338570&FileExtension=.PDF&FileName=FDR%20Data%20Subset%20(13%20Parameters)-Master.PDF - Powerplants 8 - Factual Report of Group Chairman (item 5, .PDF, 484 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332818&FileExtension=.PDF&FileName=Powerplants%208%20-%20Factual%20Report%20of%20Group%20Chairman-Master.PDF - Powerplants 8 - Attachment 1: P&W Borescope Inspection Results for Engine SN 702121 dated Sept. 29, 2008 & Nov. 12, 2008 (item 6, .PDF, 916 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332769&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%201%3A%20P%26W%20Borescope%20Inspection%20Results%20for%20Engine%20SN%20702121%20dated%20Sept.%2029,%202008%20%26%20Nov.%2012,%202008-Master.PDF - Powerplants 8 - Attachment 2: Additional borescope inspection results for Engine SN 702121 dated September 30, 2008 and an assessment of the fan case and fan blade clearance dated June 11, 2010 (item 7, .PDF, 1.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332771&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%202%3A%20Additional%20borescope%20inspection%20results%20for%20Engine%20SN%20702121%20dated%20September%2030,%202008%20and%20an%20assessment%20of%20the%20fan%20case%20and%20fan%20blade%20clearance%20dated%20June%2011,%202010-Master.PDF - Powerplants 8 - Attachment 3: P&W fan blade leading edge impressions and final evaluation for Engine SN 702121dated May 26, 2009 (item 8, .PDF, 447 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332773&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%203%3A%20P%26W%20fan%20blade%20leading%20edge%20impressions%20and%20final%20evaluation%20for%20Engine%20SN%20702121dated%20May%2026,%202009-Master.PDF - Powerplants 8 - Attachment 4: Test Plane for Engine SN 702121 Test 12 Performance Test (item 9, .PDF, 42 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332774&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%204%3A%20Test%20Plane%20for%20Engine%20SN%20702121%20Test%2012%20Performance%20Test-Master.PDF - Powerplants 8 - Attachment 5: Test 1 first run Recorded Data Engine SN 702121 (item 10, .PDF, 87 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332775&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%205%3A%20Test%201%20first%20run%20Recorded%20Data%20Engine%20SN%20702121-Master.PDF - Powerplants 8 - Attachment 6: Test 1 first run Kalitta Calculated Data Engine SN 702121 (item 11, .PDF, 76 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332777&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%206%3A%20Test%201%20first%20run%20Kalitta%20Calculated%20Data%20Engine%20SN%20702121-Master.PDF - Powerplants 8 - Attachment 7: Initial Engine Vane Position Trim Tracking Plot for Engine SN 702121 (item 12, .PDF, 61 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332778&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%207%3A%20Initial%20Engine%20Vane%20Position%20Trim%20Tracking%20Plot%20for%20Engine%20SN%20702121-Master.PDF - Powerplants 8 - Attachment 8: Test 1 second run Recorded Data Engine SN 702121 (item 13, .PDF, 87 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332780&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%208%3A%20Test%201%20second%20run%20Recorded%20Data%20Engine%20SN%20702121-Master.PDF - Powerplants 8 - Attachment 9: Test 1 second run Kalitta Calculated Data Engine SN 702121 (item 14, .PDF, 76 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332781&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%209%3A%20Test%201%20second%20run%20Kalitta%20Calculated%20Data%20Engine%20SN%20702121-Master.PDF - Powerplants 8 - Attachment 10: Newly Overhauled Fan Blade Data for Test 2 for Engine SN 702121 (item 15, .PDF, 78 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332783&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%2010%3A%20Newly%20Overhauled%20Fan%20Blade%20Data%20for%20Test%202%20for%20Engine%20SN%20702121-Master.PDF - Powerplants 8 - Attachment 11: Test 2 first run Recorded Data Engine SN 702121 (item 16, .PDF, 86 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332784&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%2011%3A%20Test%202%20first%20run%20Recorded%20Data%20Engine%20SN%20702121-Master.PDF - Powerplants 8 - Attachment 12: Engine Vibration Survey with Newly Overhauled Fan Blade and original Fan Case for Engine 702121 (item 17, .PDF, 299 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332786&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%2012%3A%20Engine%20Vibration%20Survey%20with%20Newly%20Overhauled%20Fan%20Blade%20and%20original%20Fan%20Case%20for%20Engine%20702121-Master.PDF - Powerplants 8 - Attachment 13: Test 2 first run Kalitta Calculated Data Engine SN 702121 (item 18, .PDF, 75 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332788&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%2013%3A%20Test%202%20first%20run%20Kalitta%20Calculated%20Data%20Engine%20SN%20702121-Master.PDF - Powerplants 8 - Attachment 14: Test 2 second run Recorded Data Engine SN 702121 (item 19, .PDF, 86 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332789&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%2014%3A%20Test%202%20second%20run%20Recorded%20Data%20Engine%20SN%20702121-Master.PDF - Powerplants 8 - Attachment 15: Test 2 second run Kalitta Calculated Data Engine SN 702121 (item 20, .PDF, 75 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332808&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%2015%3A%20Test%202%20second%20run%20Kalitta%20Calculated%20Data%20Engine%20SN%20702121-Master.PDF - Powerplants 8 - Attachment 16: Engine Vibration Survey with Newly Overhauled Fan Blade and New Fan Case for Engine 702121 (item 21, .PDF, 299 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332809&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%2016%3A%20Engine%20Vibration%20Survey%20with%20Newly%20Overhauled%20Fan%20Blade%20and%20New%20Fan%20Case%20for%20Engine%20702121-Master.PDF - Powerplants 8 - Attachment 17: Test 3 first run Recorded Data Engine SN 702121 (item 22, .PDF, 81 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332810&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%2017%3A%20Test%203%20first%20run%20Recorded%20Data%20Engine%20SN%20702121-Master.PDF - Powerplants 8 - Attachment 18: Test 3 first run Kalitta Calculated Data Engine SN 702121 (item 23, .PDF, 78 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332811&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%2018%3A%20Test%203%20first%20run%20Kalitta%20Calculated%20Data%20Engine%20SN%20702121-Master.PDF - Powerplants 8 - Attachment 19: Test 3 second run Recorded Data Engine SN 702121 (item 24, .PDF, 81 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332812&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%2019%3A%20Test%203%20second%20run%20Recorded%20Data%20Engine%20SN%20702121-Master.PDF - Systems 9 - Attachment 20: Test 3 second run Kalitta Calculated Data Engine SN 702121 (item 25, .PDF, 78 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332813&FileExtension=.PDF&FileName=Systems%209%20-%20Attachment%2020%3A%20Test%203%20second%20run%20Kalitta%20Calculated%20Data%20Engine%20SN%20702121-Master.PDF - Powerplants 8 - Attachment 21: Engine Vane Position Re-Trim Tracking Plot for Engine SN 702121 (item 26, .PDF, 61 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332814&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%2021%3A%20Engine%20Vane%20Position%20Re-Trim%20Tracking%20Plot%20for%20Engine%20SN%20702121-Master.PDF - Powerplants 8 - Addendum 22: Engine Re-trim Recorded Data Engine SN 702121 (item 27, .PDF, 69 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332815&FileExtension=.PDF&FileName=Powerplants%208%20-%20Addendum%2022%3A%20Engine%20Re-trim%20Recorded%20Data%20Engine%20SN%20702121-Master.PDF - Powerplants 8 - Attachment 23: Engine Re-trim Kalitta Calculated Data Engine SN 702121 (item 28, .PDF, 70 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332816&FileExtension=.PDF&FileName=Powerplants%208%20-%20Attachment%2023%3A%20Engine%20Re-trim%20Kalitta%20Calculated%20Data%20Engine%20SN%20702121-Master.PDF - Powerplants 8 - Addendum 24: P&W’s evaluation of the on-wing testing data from engine SN 702121 dated February 10, 2010 (item 29, .PDF, 1.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40332817&FileExtension=.PDF&FileName=Powerplants%208%20-%20Addendum%2024%3A%20P%26W%E2%80%99s%20evaluation%20of%20the%20on-wing%20testing%20data%20from%20engine%20SN%20702121%20dated%20February%2010,%202010-Master.PDF - Statement of Party Representatives to NTSB Investigation (item 30, .PDF, 78 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40337544&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-Redacted.PDF - Incident Delegation Emails (item 31, .PDF, 54 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40338554&FileExtension=.PDF&FileName=Incident%20Delegation%20Emails-Master.PDF From the NTSB's public API. 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