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B77W, en-route, northeast of Los Angeles USA, 2016
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|On 16 December 2016, a Boeing 777-300 which had just departed from runway 07R at Los Angeles was radar vectored in Class ‘B’ airspace at up to 1600 feet below the applicable minimum radar vectoring altitude. The Investigation found that the area controller’s initial vectoring had been contrary to applicable procedures and their communication confusing and that they had failed to recover the situation before it became dangerous. As a result, as the crew were responding in night IMC to a resulting EGPWS ‘PULL UP’ Warning, the aircraft had passed within approximately 0.3 nm of obstructions at the same altitude.|
|Actual or Potential
|Air-Ground Communication, Controlled Flight Into Terrain (CFIT), Human Factors|
|Type of Flight||Public Transport (Passenger)|
|Intended Destination||Taipei/Taiwan Taoyuan International Airport|
|Take off Commenced||Yes|
|ICL / ENR|
|Destination||Taipei/Taiwan Taoyuan International Airport|
|Approx.||Less than ½ nm south of Mount Wilson|
|Tag(s)||Extra flight crew (no training),|
Event reporting non compliant,
Delayed Accident/Incident Reporting
|Tag(s)||Incorrect Readback missed,|
|Tag(s)||IFR flight plan,|
Lateral Navigation Error,
Vertical navigation error
|Tag(s)||Inappropriate ATC Communication,|
Procedural non compliance
|Damage or injury||No|
|Causal Factor Group(s)|
|Group(s)||Air Traffic Management|
On 16 December 2016, the augmented crew of a Boeing 777-300 (B-16726) being operated by EVA Air on a scheduled international passenger flight from Los Angeles to Taipei as EVA015 received and responded to an EGPWS PULL UP Warning in night IMC whilst in receipt of radar control vectors in Class ‘B’ airspace given shortly after takeoff in a series of non standard and at times confusing instructions. After this successful recovery by the crew, the remainder of the flight to destination was completed without further event.
An Investigation into the serious incident was carried out by the NTSB with a considerable amount of the effort delegated to FAA ATO personnel. Relevant ATC radar and RTF data were available and a copy of the EGPWS NVM data from the flight was provided to the NTSB by the aircraft operator. Statements from the PF Captain and the operating First Officer were also submitted and their content was consistent with the recorded data accessed during the Investigation. Two other pilots were on board, a First Officer and a Senior First Officer.
- NB: The Final Report on this CFIT-risk incident is significantly less comprehensive than NTSB Reports on such serious events typically are and it appears that the investigation on which it is based, even allowing for reference to the contents of the supporting Docket, did not consider all aspects of the event. To assist in creating a useful summary, reference has had to be made to information from the Docket to supplement the contents of the Report. Note also that the absence in this summary of any reference to the explicit identification of systemic safety issues and the combined absence of any reference to subsequent safety action by the FAA ATO or, in the absence of this, the apparent absence of any Safety Recommendations reflect the content of both the Report and the Docket.
It was noted that until just over an hour prior to the investigated event, the airport had been operating in the usual westerly configuration but surface winds became predominantly easterly at 8 gusting to 15 knots and several aircraft making westerly approaches then went around due to an excessive tail wind component. A change to the rarely-used easterly configuration was made in response until wind velocity changed about an hour after the investigated event and the operating configuration could then be changed back to the normal westerly one.
It was established that after lining up on runway 07R, the aircraft had been given takeoff clearance on a VENTURA 7 SID. This required a climb after takeoff on a heading of 071° until receiving radar vectors to the VTU VOR/DME. Shortly after the aircraft became airborne, it was transferred to the applicable Southern California TRACON (SCT) sector frequency and, on checking in there and reporting passing 1,900 feet for 5,000 feet having been airborne for approximately 3 minutes, was instructed to climb and maintain 7,000 feet and fly heading 090° which was correctly acknowledged. The first illustration below shows the ground track flown by the aircraft from takeoff until safely established southbound.
One minute later, the controller instructed the flight to “turn left heading of 180, climb and maintain 7,000" which would have required a 270° turn. When acknowledging this, a "high speed climb" was requested and approved. As the aircraft commenced this (additional radius) left turn, the controller then instructed it to "turn right, right turn heading one eight zero" which was acknowledged and as the right turn began the controller transmitted to the 777 “expedite your right turn” to which the flight replied with “[unintelligible] passing heading 010, continue heading”.
Aware of a Boeing 787-8 which needed to be de-conflicted from the 777, the controller then made a series of transmissions in quick succession, not allowing much time in between except for a read back:
- to an Air Canada Boeing 787-8 that was about 5½ nm west of the 777 to expedite its climb and turn left heading 360°
- to the 777, which had just passed 5000 feet climbing as previously cleared to 7000 feet to "stop your climb"
- to the 787 to “expedite to 12,000 feet”
- to the 777 to "turn left, left turn to a heading of ah, two nine ah, correction two seven zero" which was acknowledged correctly
- to the 777 “what are you doing, turn southbound now, southbound now, stop your climb" to which the flight replied "confirm EVA015 heavy, maintain 5,000, left, right, right heading [unintelligible]".
The controller then called the Los Angeles arrivals sector controller and requested a “point out” on the 777 which was approved along with a caution to “watch out for the minimum vectoring altitudes (MVAs) due to rising terrain”.
- NB: the non-ICAO term ‘Point Out’ is used by the FAA ATO to mean “a physical or automated action taken by a controller to transfer the radar identification of an aircraft to another controller if the aircraft will or may enter the airspace or protected airspace of another controller and radio communications will not be transferred”. The term ‘Point Out Approved’ is used to inform the controller initiating a point out that the aircraft is identified and that approval is granted for the aircraft to enter the receiving controller's airspace, as coordinated, without a communications transfer or the appropriate automated system response.
Immediately after this, the 777, now south east of Pasadena (see the illustration below) and continuing in a left turn requested confirmation of the assigned heading and received the response "turn southbound, southbound now" which was read back as given. Twenty seconds later, the 777 began to change from a left turn to a right turn, taking it towards 5,700 feet high Mount Wilson which had several tall masts on its southern flank, the tallest being 970 feet. The MVA for this area was 7,800 feet.
Thirteen seconds after the right turn had commenced, the controller instructed the 777 to "climb and maintain five thousand, and ah, are you, are you southbound now, I see you going northbound, climb and maintain six thousand" and received the response "roger, turning ah, we are turning south and ah maintain five thousand” but the incorrect altitude read back was not challenged. After stopping her transmissions to the 777 just long enough to tell Los Angeles TWR to stop departures, she then immediately re-cleared the 777 to "climb and maintain seven thousand" which was correctly acknowledged.
Almost immediately, with the aircraft passing north as it continued turning right, the visual Low Altitude (LA) Alert on the controller’s radar display was activated. Immediately after this began, the controller transmitted to the 777 “I see you're going southbound, turn south, correction I see you going northbound now, turn south now, climb and maintain seven thousand" to which there was no response. A repeat of the instruction received the response "[unintelligible] right turn to southbound, continue climb seven thousand" followed by a re-iteration "continue right turn and ah climb to seven thousand to a heading one eight zero". Eight seconds after the ATC LA Alert had begun, an EGPWS ‘Caution Terrain’ alert was activated on the 777 for 4 seconds and after an 8 second gap, repeated for a further 4 seconds. The aircraft was climbing towards rising terrain as it continued its right turn to approach and then pass just south of the summit of Mount Wilson. Four seconds after the second of these terrain alerts, with the aircraft continuing to turn right, passing through northeast and climbing through approximately 5,200 feet in IMC, an EGPWS PULL UP Warning began. The crew responded immediately by disconnecting the AP, pitching up and increasing thrust from 79% NI to 93% N1. The Warning continued for 7 seconds, during which time the aircraft rate of climb increased from 1,500 fpm to 3,200 fpm. Thereafter, the turn was continued and high thrust was maintained and due to the height gained in response to the PULL UP Warning, there were no further EGPWS activations. The illustration below shows the aircraft ground track annotated with time and aircraft altitude beginning just as the PULL UP Warning ceases at 5,400 feet. It can be seen that the aircraft then just avoids a number of TV masts rising respectively to 6,630 feet amsl, 6,112 feet amsl, 6,174 feet amsl and 6,224 feet amsl. The last of these is the one which the aircraft came closest to and it was approximately 0.3 nm away as the aircraft passed through a recorded 6,300 feet.
The controller’s LA Alert continued for 75 seconds during which time there were no further communications between the 777 and the controller although they again instructed Los Angeles TWR to stop departures.
About a minute after the LA Alert had ceased, the 777 called reporting on heading 180° at 7,000 feet and received in response an instruction to "climb and maintain, ah maintain seven thousand". Upon levelling at 7000 feet on the heading 180°, the AP had been re-engaged. The Captain sought to query with the controller the unexpected left turn instruction which had been given on departure and the response was reported as having been “they will look into that”. There were no further exchanges relevant to the event between the 777 and the sector controller involved or any subsequent controller.
Unrelated in any direct way to the event under investigation, it nevertheless noted that whilst the sector controller was vectoring the 777, another aircraft went around from an approach to runway 09R and when TWR requested an initial heading and level for it, the sector controller gave “090° to stop at 2,000 feet” which was contrary to easterly procedures which required a climb to 3,000 feet and differed from the westerly go around procedure which did require the climb to stop at 2,000 feet. As a result, this other aircraft entered an area with a 2,700 MVA at 2,000 feet.
The Investigation focused almost exclusively on the performance of the TRACON sector controller involved and relied heavily on related FAA investigations carried out within the unit involved. The performance of the 777 flight crew was not examined other than superficially but on the strength of the information available, in particular the EGPWS data download provided by EVA Air and included in the NTSB Docket for the Investigation, there was no evidence that it had contributed to the event other than through understandable confusion caused to a foreign flight crew without English as their native language by the controller’s issue of inappropriate, poorly specified and needlessly repetitive instructions throughout.
In respect of the controller’s performance, it was noted that she had been certified for all SCT positions since 2014 and was designated as an OJTI. It was also noted that although annual refresher training on the rarely-used Los Angeles easterly configuration including both briefings and the working of simulation scenarios was mandatory, the controller involved had not completed these required simulations. It was noted that SCT Unit SOPs required that all easterly departures from Los Angeles routed to the VTU VOR were to be given a right turn onto a radar heading of 250° and climbed on that heading to 13,000 feet or above.
In respect of the reporting of the occurrence, the Investigation found considerable evidence that there had been an attempt to play down the safety significance of the investigated event within the FAA. Although an internal MOR was submitted by the SCT TRACON duty Operations Manager later the same day via the FAA Regional Operations Centre, it was determined on review by the responsible person in the “Compliance Services Group” that “the incident was not serious enough to warrant a services rendered telecon (SRT) and no further reporting of the incident would be required”. It was noted that the required calculation of the incident’s Measure of Compliance (MOC) was not made during this review whereas “according to the FAA, any reported or detected loss of separation between other aircraft or terrain and obstructions that falls below 66% of the required separation is considered a risk analysis event (RAE) and an SRT may be initiated”.
The controller involved did not complete an Air Traffic Safety Action Program (ATSAP) Report within the required 24 hours and the FAA declined to disclose to the Investigation whether the report eventually submitted had been accepted by the Event Review Committee (ERC). On the evidence presented, the effectiveness of both the FAA ATO Quality Assurance Program (QAP) and its Quality Control Program (QCP) in ensuring an appropriate response to the event and in particular ensuring a meaningful assessment of its seriousness, appeared to be in some doubt. Not until three days after the event was an SRT conducted and concluded that the aircraft had flown “within 0.5 nm laterally, and below the published and charted altitude of a displayed obstruction”.
The Probable Cause of the event was determined to be “the air traffic controller assigning the pilots a left turn instead of the required right turn after departure which placed the aircraft in an unsafe proximity with terrain and obstructions”.
A Contributory Factor was identified as “the air traffic controller's inadequate recovery technique during the development of the incident”.
The Final Report of the Investigation was published on 7 May 2019. The associated Docket from which detail not included in the Final Report has been taken in order to prepare this summary was released online the day prior to publication of the Report. No Safety Recommendations were made.