Airprox Report 2013086

1
AIRPROX REPORT No 2013086
Date/Time: 19 Jul 2013 1835Z
Position: 5126N 00058W
(19.5nm W LHR)
Airspace: Lon UIR (Class: C)
Reporting Ac Reported Ac
Type: A320 Unknown
Operator: CAT NK
Alt/FL: FL340 NK
Weather: NK NK
Visibility: NK NK
Reported Separation:
NK NK
Recorded Separation:
NK
PART A: SUMMARY OF INFORMATION REPORTED TO UKAB
THE A320 PILOT reports transiting in level cruise at FL340, just to the west of Heathrow. The First
Officer (FO) in the RH seat, was looking down at the PLOG1. The Captain, in the LH seat, looked to
the West out of the flight deck ‘Direct Vision’2 window. As he turned to look ahead, he perceived an
object travelling towards them, at what appeared to be the same level, slightly above the flight deck
windscreen. Having very little time to focus, he was under the apprehension that they were on a
collision course with no time to react. His immediate reaction was to duck to the right and reach over
to alert the FO; there was no time to talk to alert him. The FO turned and looked at him, thinking
something was wrong with the aircraft. The Captain was fully expecting to experience some kind of
impact with a conflicting aircraft. His first words to the FO were, “did you see that”, who replied, “see
what”. The Captain perceived an object pass within a few feet above the aircraft. It could best be
described as cigar/rugby ball like in shape, bright silver, and metallic like in construction. His first
reaction after gathering his thoughts, was to interrogate the TCAS for returns within the area; none
were seen. He then asked ATC for information on any aircraft in the vicinity, again there were no
known aircraft in the area at the time and no other primary or secondary returns. He explained the
situation to ATC and the crew both decided they would file an Airprox. Upon arriving at the
destination, the Captain spoke extensively by phone with the ATC watch manager for that sector.
The UK Airprox Board Secretariat was unable to trace the other aircraft.
Factual Background
At 1835 on 19 Jul 2013 at the position of CPA, the sun was at a bearing of 278° and elevation 21° at
ground level3. This equates to an elevation of about 24° at FL340.
1 An abbreviation for Progress or Pilot’s Log. The PLOG is a tabular record which includes information such as planned
track, heading, altitude, ETA and fuel state for each leg of the journey. Information such as actual track, heading, altitude,
ETA and fuel state is completed as the flight progresses and is used to assess the safe progress of the flight.
2 The Direct Vision (DV) window, also known as the Direct Ventilation window, is a part of the windscreen that can be
opened should direct vision be required, e.g. in the event of windscreen obscuration the pilot can open the DV window and
look ‘directly’ outside, rather than attempt to judge a landing through the obscured windscreen.
3 As a guide, with a hand held at arm’s length, back of the hand facing you and fingers spread as wide as possible, the span
from little finger to thumb subtends an angle of 20°-25°.Diagram based on radar data
and pilot report
A320
FL340
CPA 1835