# NTSB ERA13LA022: Hughes/Helicopter Assocs 369A, N546, West Chester, PA, October 13, 2012 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: October 13, 2012, 09:20 local (13:20 UTC) - Place: West Chester, PA - Coordinates: 39.990276, -75.581947 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.9903&lon=-75.5819&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining events: [Maneuvering-hover: Midair collision](https://openairdocs.org/ntsb-events/250); [Maneuvering-hover: Midair collision](https://openairdocs.org/ntsb-events/250) - Highest injury: No injuries - Injuries: 5 uninjured - Status: Completed, report March 14, 2016 - Report: Approved by Office Director - NTSB office: Eastern Region Aviation - Parties: FAA/FSDO - NTSB case key (mKey): 85324 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA13LA022 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/85324/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=85324 - Page: https://openairdocs.org/ntsb/ERA13LA022 ## Probable cause (aircraft 1) The pilot’s failure to see and avoid the preceding helicopter while maneuvering for landing. Contributing to the accident were the flight lead pilot’s inadequate preflight briefing and in-flight instruction to the formation pilots, which resulted in the loss of the formation flight's integrity and the pilots’ situational awareness within the flight. ## Probable cause (aircraft 2) The other pilot’s failure to see and avoid the preceding helicopter while maneuvering for landing. Contributing to the accident were the flight lead pilot’s inadequate preflight briefing and in-flight instruction to the formation pilots, which resulted in the loss of the formation flight's integrity and the pilots’ situational awareness within the flight. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Attention/monitoring: monitoring other aircraft](https://openairdocs.org/ntsb-findings/02021540): Personnel issues › Psychological · Pilot (probable cause), aircraft 1; cases with it: [Hughes/Helicopter Assocs 369A, 1 case](https://openairdocs.org/ntsb-findings/02021540/cases.md?model=4470703), [All aircraft, 231 cases](https://openairdocs.org/ntsb-findings/02021540/cases.md) - [Planning/preparation: flight planning/navigation](https://openairdocs.org/ntsb-findings/02061025): Personnel issues › Task performance · Not specified (probable cause), aircraft 1; cases with it: [Hughes/Helicopter Assocs 369A, 1 case](https://openairdocs.org/ntsb-findings/02061025/cases.md?model=4470703), [All aircraft, 179 cases](https://openairdocs.org/ntsb-findings/02061025/cases.md) - [Attention/monitoring: monitoring other aircraft](https://openairdocs.org/ntsb-findings/02021540): Personnel issues › Psychological · Pilot of other aircraft (probable cause), aircraft 2; cases with it: [Hughes OH-6A, 1 case](https://openairdocs.org/ntsb-findings/02021540/cases.md?model=4470905), [All aircraft, 231 cases](https://openairdocs.org/ntsb-findings/02021540/cases.md) - [Planning/preparation: flight planning/navigation](https://openairdocs.org/ntsb-findings/02061025): Personnel issues › Task performance · Not specified (probable cause), aircraft 2; cases with it: [Hughes OH-6A, 1 case](https://openairdocs.org/ntsb-findings/02061025/cases.md?model=4470905), [All aircraft, 179 cases](https://openairdocs.org/ntsb-findings/02061025/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering-hover: Midair collision](https://openairdocs.org/ntsb-events/250) (defining event), aircraft 1; cases with it: [Hughes/Helicopter Assocs 369A, 1 case](https://openairdocs.org/ntsb-events/250/sequence.md?model=4470703), [All aircraft, 196 cases](https://openairdocs.org/ntsb-events/250/sequence.md) - [Maneuvering-hover: Midair collision](https://openairdocs.org/ntsb-events/250) (defining event), aircraft 2; cases with it: [Hughes OH-6A, 1 case](https://openairdocs.org/ntsb-events/250/sequence.md?model=4470905), [All aircraft, 196 cases](https://openairdocs.org/ntsb-events/250/sequence.md) ## Analysis (aircraft 1) The formation flight of helicopters, designated Chalk 1 through 5, was en route to an annual airshow. The lead helicopter (Chalk 1) was on the left base leg of the traffic pattern at the nontower-controlled destination airport when the Chalk 3 helicopter pilot identified and announced that an airplane was on final approach for the landing runway. The Chalk 1 helicopter pilot announced that he was conducting a go-around and turned the helicopter left, inside the landing runway, and proceeded upwind. About the same time, the flight lead pilot, who was traveling in the trail position (Chalk 5), instructed the other helicopter pilots to "break left or land." The flight lead pilot's ambiguous instruction resulted in the breakdown of the formation flight's integrity. Instead of a flight of five helicopters and one airplane attempting to avoid conflict in the traffic pattern, each of the six individual aircraft were immediately placed in a position in which the pilots had to avoid potential collisions with the other aircraft. The Chalk 4 pilot subsequently lost sight of the Chalk 3 helicopter as the pilots of both helicopters were maneuvering for landing. The Chalk 4 helicopter pilot then landed the helicopter and was hover-taxiing to park when the helicopter collided with the Chalk 3 helicopter as its pilot was maneuvering it to land on the runway. Before the flight, the flight lead pilot presented briefing slides to the group of pilots; however, the slides did not provide any procedures for a loss of visual contact while flying in formation. ## Analysis (aircraft 2) The formation flight of helicopters, designated Chalk 1 through 5, was en route to an annual airshow. The lead helicopter (Chalk 1) was on the left base leg of the traffic pattern at the nontower-controlled destination airport when the Chalk 3 helicopter pilot identified and announced that an airplane was on final approach for the landing runway. The Chalk 1 helicopter pilot announced that he was conducting a go-around and turned the helicopter left, inside the landing runway, and proceeded upwind. About the same time, the flight lead pilot, who was traveling in the trail position (Chalk 5), instructed the other helicopter pilots to "break left or land." The flight lead pilot's ambiguous instruction resulted in the breakdown of the formation flight's integrity. Instead of a flight of five helicopters and one airplane attempting to avoid conflict in the traffic pattern, each of the six individual aircraft were immediately placed in a position in which the pilots had to avoid potential collisions with the other aircraft. The Chalk 4 pilot subsequently lost sight of the Chalk 3 helicopter as the pilots of both helicopters were maneuvering for landing. The Chalk 4 helicopter pilot then landed the helicopter and was hover-taxiing to park when the helicopter collided with the Chalk 3 helicopter as its pilot was maneuvering it to land on the runway. Before the flight, the flight lead pilot presented briefing slides to the group of pilots; however, the slides did not provide any procedures for a loss of visual contact while flying in formation. ## Factual narrative (aircraft 1) On October 13, 2012, about 0920 eastern daylight time, two helicopters in a flight of five, a Hughes 369A, N369SN (Chalk 3), and another Hughes 369A, N546 (Chalk 4), collided during hover-taxi while landing at Brandywine Airport (OQN), West Chester, Pennsylvania. The 3 occupants in Chalk 3 and the 2 occupants in Chalk 4 were not injured. Chalk 4 sustained substantial damage to all four main rotor blades and the tail pylon. Chalk 3 sustained substantial damage to the left landing skid. Both helicopters were operated under the provisions of 14 Code of Federal Regulations Part 91as personal flights. Visual meteorological conditions prevailed.The flight of helicopters, each designated "Chalk 1" through "Chalk 5," were enroute to an annual all-helicopter airshow. The pilots of Chalk 1, 3, and 4 provided written statements, and their statements were consistent throughout. They each said that "Flight Lead," Chalk 5 was flying in the trail aircraft position. According to their statements, the flight arrived in trail formation and overflew runway 09 at 1,200 feet and 60 knots. Chalk 1 stated he entered left traffic, and while on the left base leg for landing, Chalk 3 announced airplane traffic on final approach to Runway 09. Chalk 1 stated he turned left prior to the runway, and initiated a go-around on the north side of the runway. Flight lead, in the trail aircraft, then announced over the flight's internal radio frequency to, "Break left or land." According to Chalk 3, he then "initiated a steep approach" to land on runway 09, and while he maintained visual separation from Chalk 2, noticed the rotor disk of another helicopter immediately below and to the right of his just as contact between the two was made, which separated the left landing gear skid. Chalk 3 then egressed his passengers from a hover, and repositioned the helicopter back to LNS and sought the assistance air traffic control (ATC) and crash/fire/rescue services. The helicopter landed without further incident. According to Chalk 4, Chalk 1 announced a go-around, but Chalk 5 gave the command to break left or land. At that point, he had Chalks 1, 2, and 3 in sight. Chalk 4 then confirmed the airplane traffic was "no factor" and had initiated a go-around on the south side of the runway. When he looked back on the formation in front of him, he had only Chalk 2 in sight, and had lost visual contact with Chalks 1 and 3. Chalk 4 then performed a "normal" approach to a 5-foot hover over the runway centerline, began a hover-taxi to parking, and about 20 seconds later "felt" the contact with the other helicopter. He then landed the helicopter without further incident. The pilot of Chalk 4 held a private pilot certificate, with a rating for a rotorcraft-helicopter. He reported 586 total hours of flight experience, of which 253 hours were in the accident helicopter make and model. The pilot of Chalk 3 held a commercial pilot certificate, with a rating for a rotorcraft-helicopter. He reported 1,617total hours of flight experience, 92 hours of which were in the accident helicopter make and model. Each of the accident helicopters had 100-hour inspections performed during the year prior to the accident, and each pilot reported there were no mechanical deficiencies with either helicopter that would have prevented normal operation. Examination of briefing slides provided to the group by the flight lead (Chalk 5) revealed that the aircraft position order briefed on the slides was not the order flown. There were no slides that provided guidance for loss of visual contact or an inadvertent encounter with instrument meteorological conditions. There was no slide that identified flight lead would fly from the trail position of the formation. ## Factual narrative (aircraft 2) On October 13, 2012, about 0920 eastern daylight time, two helicopters in a flight of five, a Hughes 369A, N369SN (Chalk 3), and another Hughes 369A, N546 (Chalk 4), collided during hover-taxi while landing at Brandywine Airport (OQN), West Chester, Pennsylvania. The 3 occupants in Chalk 3 and the 2 occupants in Chalk 4 were not injured. Chalk 4 sustained substantial damage to all four main rotor blades and the tail pylon. Chalk 3 sustained substantial damage to the left landing skid. Both helicopters were operated under the provisions of 14 Code of Federal Regulations Part 91as personal flights. Visual meteorological conditions prevailed. The helicopters were part of a flight of 5 helicopters that attended an annual all-helicopter airshow.The pilots of Chalk 1, 3, and 4 provided written statements and their statements were consistent throughout. They each said that "Flight Lead" was in Chalk 5; the trail aircraft. According to their statements, the flight arrived in trail formation and overflew runway 09 at 1200 feet and 60 knots. Chalk 1 stated he entered left traffic, and while on the left base leg for landing, Chalk 3 announced airplane traffic on final approach to Runway 09. Chalk 1 stated he turned left prior to the runway, and initiated a go-around on the north side of the runway. Flight lead, in the trail aircraft, then announced over the flight's internal radio frequency to, "Break left or land." According to Chalk 3, he then "initiated a steep approach" to land on runway 09, and while he maintained visual separation from Chalk 2, noticed the rotor disk of another helicopter immediately below and to the right of his just as contact between the two was made, which separated the left landing gear skid. Chalk 3 then egressed his passengers from a hover, and repositioned the helicopter back to LNS in order to avail him of air traffic control and crash/fire/rescue services. The helicopter landed without further incident. According to Chalk 4, Chalk 1 announced a go-around, but Chalk 5 gave the command to break left or land. At that point, he had Chalks 1, 2, and 3 in sight. Chalk 4 then confirmed the airplane traffic was "no factor" and had initiated a go-around on the south side of the runway. When he looked back on the formation in front of him, he had only Chalk 2 in sight, and had lost visual contact with Chalks 1 and 3. Chalk 4 then performed a "normal" approach to a 5-foot hover over the runway centerline, began a hover-taxi to parking, and about 20 seconds later "felt" the contact with the other helicopter. He then landed the helicopter without further incident. The pilot of Chalk 4 held a private pilot certificate, with a rating for a rotorcraft-helicopter. He reported 586 total hours of flight experience, of which 253 hours were in the accident helicopter make and model. The pilot of Chalk 3 held a commercial pilot certificate, with a rating for a rotorcraft-helicopter. He reported 1,617 total hours of flight experience, 92 hours ofwhich were in the accident helicopter make and model. Each of the accident helicopters had 100-hour inspections performed during the year prior to the accident, and each pilot reported there were no mechanical deficiencies with either helicopter that would have prevented normal operation. Examination of the Rotorfest 2012 Briefing slides revealed that the Chalk order briefed on the slides was not the Chalk order flown. There was no slide that provided guidance for loss of visual contact or inadvertent IMC procedures. There was no slide that identified "Flight Lead" would fly from the trail position of the formation. Examination of military and Formation and Safety Team (FAST) training documents revealed that flight lead was always the lead aircraft in a given multi-ship formation. While the air mission commander (AMC) may fly from any position in the formation, the lead aircraft always maintained the role of flight lead. Following in-flight formation changes, the aircraft assuming the lead position in the flight, assumed the role of flight lead. Army Field Manual (FM 3-04.203) Fundamentals of Flight, Chapter 6, Multi-Aircraft Operations stated: FLIGHT LEAD (TEAM LEAD) 6-8. Flight (team) lead and wingman are roles flight members fulfill based upon their positions within the flight. Team lead is used to denote the flight lead for two aircraft operating in teams. Flight lead is the formation leader designated by the AMC and is generally the most proficient PC (pilot in command). Flight leads are selected based on ability and demonstrated knowledge of missions and tactics, and local SOPs. The flight lead's responsibilities include navigation, en route communication (between flight members, ATC, and supported units), obstacle and threat avoidance, wingmen position awareness, and the energy states of all aircraft. The AMC may delegate some of these duties throughout the flight. Chalk 2 should always be prepared to lead the flight. FORMATION LANDING 6-41. All aircraft touch down at the same time while maintaining their relative positions within the flight. The rate of closure throughout approach and landing is somewhat slower at night than during the day. Flight lead should maintain straight-and-level flight until the desired approach angle is intercepted. Lead then maintains a constant approach angle and, where terrain and obstacles permit, makes the approach to the ground avoiding hovering turbulence and brownout or whiteout conditions. If the rate of closure is too fast, the aviator should avoid S-turns to lose airspeed. Instead, execute a go-around if unable to slow to the appropriate airspeed, especially with heavily loaded aircraft. 6-42. Lead must plan to touch down far enough forward in the PZ/LZ to provide sufficient landing space for the entire flight. ## Aircraft 1 - Registration: [N546](https://openairdocs.org/aircraft/N546), registered now, S/N HA001, built 1997 (OpenAirDocs) - Reported make and model: HUGHES/HELICOPTER ASSOCS INC 369A - Registry model: [Hughes/Helicopter Assocs 369A](https://openairdocs.org/model/hughes-helicopter-assocs-369a) (registry code 4470703) (OpenAirDocs) - Registry engine: [Allison 250-C10D](https://openairdocs.org/engine/allison-250-c10d) (registry code 03035, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: HA001 - Year built: 1997 - Airframe hours: 1154 - Engines: Rolls-Royce 250-C10D 317 horsepower turbo shaft - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, December 31, 2011, 94 hours before - Departed: LNS, Lancaster, PA - Destination: OQN, West Chester, PA - Airport: OQN, Brandywine, runway 09, 3,347 × 50 ft, asphalt ## Aircraft 2 - Registration: [N369SN](https://openairdocs.org/deregistered/N369SN-2019-05-08), registration cancelled 2019-05-08, S/N 66-14389, built 1968 (OpenAirDocs) - Reported make and model: HUGHES 369A - Registry model: [Hughes OH-6A](https://openairdocs.org/model/hughes-oh-6a) (registry code 4470905) (OpenAirDocs) - Registry engine: [Rolls-Royce 250-C10D](https://openairdocs.org/engine/rolls-royce-250-c10d) (registry code 54172, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 66-14389 - Year built: 1968 - Airframe hours: 4386 - Engines: Allison/RR 250-C10D 317 horsepower turbo shaft - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, October 8, 2012 - Departed: LNS, Lancaster, PA - Destination: OQN, West Chester, PA - Airport: OQN, Brandywine, runway 09, 3,347 × 50 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot, aircraft N546; age 57; injuries: none; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; last flight review February 28, 2012; seat: right; flight hours: 586 total, 253 in this make and model, 379 as pilot in command, 32 in the last 90 days, 17 in the last 30 days, 3 in the last 24 hours - Pilot, aircraft N369SN; age 49; injuries: none; private, commercial, flight instructor; airplane ratings: single-engine land; medical: class 2, with waivers/limitations; last flight review April 2, 2012; seat: right; flight hours: 1,617 total, 92 in this make and model, 1,458 as pilot in command, 29 in the last 90 days, 22 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 43 °F - Altimeter: 30.53 inHg - Observed at: LNS, 35 nm away ## FAA reports on this event (2) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20121013023652A](https://openairdocs.org/incident/20121013023652A), Oct 13, 2012: Hughes/Helicopter Assocs Inc 369A, West Chester, PA, Substantial damage. On Saturday, October 13, 2012, at approximately 0920 local time, a five-ship formation of helicopters from lancaster airport, PA (lnr) arrived to conduct… - [Accident 20121013023732A](https://openairdocs.org/incident/20121013023732A), Oct 13, 2012: Hughes OH-6A, West Chester, PA, Substantial damage. On Saturday, October 13, 2012, at approximately 0920 local time, a five-ship formation of Hughes 500 helicopters from lancaster airport, PA (lnr) arrived to… ## Docket (7 files) The files NTSB released with the investigation on February 3, 2016, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=85324. 4.0 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 Chalk 3 Report (item 1, .PDF, 916 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40436329&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1%20Chalk%203%20Report-Master.PDF - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 Chalk 4 Report (item 2, .PDF, 797 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40436330&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1%20Chalk%204%20Report-Master.PDF - Weather Reports and Records (item 3, .PDF, 128 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40436331&FileExtension=.PDF&FileName=Weather%20Reports%20and%20Records-Master.PDF - Witness Statements - Pilot of Chalk 1 (item 4, .PDF, 94 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40436333&FileExtension=.PDF&FileName=Witness%20Statements%20-%20Pilot%20of%20Chalk%201-Master.PDF - Witness Pilot of Chalk 5 Statement (item 5, .PDF, 85 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40436334&FileExtension=.PDF&FileName=Witness%20Pilot%20of%20Chalk%205%20Statement-Master.PDF - Witness Student Pilot in Chalk 3 (item 6, .PDF, 59 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40436335&FileExtension=.PDF&FileName=Witness%20Student%20Pilot%20in%20Chalk%203-Master.PDF - Photographs (item 7, .PDF, 7 photos, 1.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40436332&FileExtension=.PDF&FileName=Photographs-Master.PDF From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.