2008 TC₃ - Eyewitness accounts of the final moments by pilots of KLM-592

On this page:

Picture of Captain de Poorter and Jacob Kuiper
Background by Jacob Kuiper
Account of Captain de Poorter
Additional details from co-pilot van Uden
 

copyright 2008 Jacob Kuiper
Captain Ron de Poorter (left) and Jacob Kuiper (right)

As General Aviation meteorologist at the Royal Netherlands Meteorological Institute I was on duty during the night of Oct 6-Oct 7th. One of my tasks is informing the international aviation about hazardous weather and volcanic ash clouds at their flight routes. In particular I am informing Air-France – KLM by briefing KLM-operations at Schiphol airport in Amsterdam. Also that night I had a briefing with KLM-dispatch at the beginning of my shift (Oct 6th, around 2200 UTC).

After that briefing I opened my email box to look what has been received last hours. Some emails, received just in the last hour, took my attention immediately. An asteroid, just discovered last morning, should impact earth atmosphere in the early hours of Oct 7th. Reading it again to be sure I hadn’t made a mistake reading it too quick, I realised that this should be a unique event in history of asteroid/meteor-astronomy. For the first time an impact in the atmosphere of an extraterrestrial body, discovered before it had reached our planet..

Some of these mails showed the forecasted impact coordinates, 20.5 degrees North and 33.1 degrees East, somewhere in the north of Sudan. I also realised that the fiery entrance should not be visible from the Netherlands but with this clear conclusion I was not satisfied. What could I do more with this information? What was the weather/cloud situation in the specific impact area? What means did I have to get more data of this special event, happening a few hours from now?

These questions continuously circled through my mind. It would be nice if direct eyewitness reports from that area should be collected. It could possibly give a good contribution to the verification of what computer models had produced. And then, about 40 minutes before impact time of 2008 TC3 I realised that I could ask some assistance of my KLM dispatchers. Their international airliners fly almost daily over the African continent. One phone call with one of their officials was enough. I explained what was going on about the asteroid, coordinates, possible visible phenomena, time (0246 UTC was mentioned) were given. The official said that there were indeed some KLM airliners over Africa. He should inform them and if a crew should see something, he would quickly report it to me.

0246 UTC passed, I was eager if there should be a report. And… 15 minutes later the phone… KLM dispatch! “We have a confirmation about your asteroid-case! KLM-592 has seen a bright flash just a few moments before 0246 UTC. The plane was at that moment in the northern part of Chad, in the so-called N’Djamena FIR.

A Flight Information Region (FIR) is an aviation term used to describe airspace with specific dimensions, in which a Flight Information Service and an alerting service are provided. It is the largest regular division of airspace in use in the world today.

The distance between the plane and the forecasted impact area was almost 1500 km, quite far, but the light flashes seen by the captain and his co-pilot were unmistakably close to the time and position what they expected.” In the last part of my shift I was able to make a small report of what had taken place and I sent it to the webmaster of Spaceweather.com which website I visit daily (since the end of the ‘60s I am very interested in everything what has to do with space research/travel, astronomy, and special phenomena in earth’s atmosphere and aloft. When I was 12 the first landing on the moon boosted that hobby a lot and it never left.).

The next night I asked the KLM dispatcher again about the observation of the pilots of KLM-592, also reporting that the observation of their crew has been received by the international astronomy authorities very well and that till that moment no further direct eyewitness reports had been received. I said the official that I liked to have a direct contact with the pilots to hear their story personally. He was cooperating very well and sent an email to them with my request. October 8th the captain of the plane called me by phone in the afternoon. He gave a very detailed report of what he had seen. It was possible to arrange another direct talk at Friday Oct 11th at my house.

(interview with Captain de Poorter appears below)

Captain Ron de Poorter and co-pilot Coen van Uden were flying their 747-400 from Johannesburg to Amsterdam during that night of Oct 6th -7th. When they received the alert-message about 2008 TC₃ from KLM dispatch, their position was over Chad. At 0244 UTC they passed position NAMAD, on airway UM215, on the way to waypoint TONBA.

From that moment on, both pilots continuously observed the horizon in the east-north-east sector of their sight. They had put the received coordinates in their navigation system and concluded that, compared to their plane’s heading (which was at that moment 348 degrees, almost NNW), they had to look at a bearing of 68-70 degrees, in clockwise terms looking at ‘half past two’. The plane flew at that moment at FL340.

A Flight Level (FL) is a standard nominal altitude of an aircraft, in hundreds of feet. Flight levels are described by a number, which is this nominal altitude ("pressure altitude") in feet, divided by 100. Therefore an apparent altitude of 34,000 feet is referred to as "flight level 340" or FL340.

At UTC 0245+40 seconds they saw the sky above the part of the horizon they were looking at, suddenly brightening by a light flash. In approximately one and a half second, 2 to 3 times this ‘lightning’ was visible. The direct ‘meteor’ was not visible, because of their large distance to the atmosphere entrance point and possibly due to some absorption of light in the thick atmosphere layers in the lowest degree above the horizon (Comment by JK: on the Meteosat-9 IR-image of 0300 UTC some medium and higher clouds are visible between the plane’s position and the impact point. Probably these clouds over NW-Sudan could have masked the ‘highest’ part of the meteor-trail a bit from their viewing point).

The illumination of the sky looked like the firing of artillery far away in such a way that only the sky is exposed to light flashes or like distant thunder lighting the sky. The colour of these flashes was yellowish and reddish but certainly not white, as someone should expect. (Comment by JK: also the extinction of light in dense atmosphere layers just above the horizon could be a good explanation of the mentioned colours). The dome of light was visible over at least 10 degrees along the horizon, 5 degrees to each side of the central area of the phenomenon. At the moment of observation the whole eastern sky was almost dark, maybe in the southeast a little bit showing the first taints of twilight. Co pilot Van Uden, at the right part of the cockpit had the best view to this phenomenon, but also captain De Poorter had a clear sight to that part of the sky. Only some weak lights of the instrumental panel were in the lower foreground of his sight, but they didn’t hamper his observation at all.

After that sighting everything turned back to normal. De Poorter said that the light-flashes were very easy to see but he wondered if he and his co pilot should have seen them if they were not warned before. Because of their looking at the forecasted position everything was easy to see, if that shouldn’t have been the case they could have missed it also easily.

The plane was flying at point NAMAD at a groundspeed of 498 knots; the wind at their height was forecasted to be light from the northeast (around 050 degrees with 6 knots). The position of KLM-592 at the moment of observation was approximately 12 miles north of NAMAD, in Lat Lon coordinates, around 15 degrees 12 min Northern Latitude and 20 degrees 45 min Eastern Longitude.

One important remark of Captain De Poorter when he was telling his story:

It should be very interesting to make an announcement in the international aviation community for pilots who have possibly seen this entrance from much closer distance. Between Cairo and Khartoum are a few airways which are very busy, also in the night-time. Airways, A/UA727 and A/UA451D are situated almost under the entrance point of the asteroid. An international announcement probably could result in more detailed observations which could give a fine contribution to the currently known satellite-, infrasound- data and our own observation.

(This account was written by Jacob Kuiper in November 2008)

Due to holidays it lasted a few weeks before I was able to contact the second eyewitness Mr. Coen van Uden. I asked Mr. van Uden to tell his story, before I should ask him specifically at certain details. This purely to have the most objective report possible.
After telling his story I am concluding that in general the report of Mr. Van Uden is consistent with that of Mr. de Poorter. But, when I asked him about some details of the sighting, some differences in the answers of Mr. van Uden appeared, when I compared them to that of Mr. De Poorter.

At my question how long the light ’flashes’ have been visible, Mr. van Uden answered 4 to 5 seconds. And the width of the light effect along the horizon has been visible over approximately 20 degrees. The maximum height above the horizon where some light effects were noted has been estimated to 10 degrees. Mr. Van Uden thought that he had seen 2 ‘maxima’ in the light reflection in the atmosphere.

Comparing those facts with that of the captain’s observation I have some ideas to explain the differences between reports of the 2 observers.

First there is the position of each pilot in the cockpit. Mr. Van Uden, seated at the right side, had the best viewing point. He could look freely through the window without being hindered by any instrument lights. Mr De Poorter at the left seat, had to look to the right with some, but already quite strongly dimmed, instrument panel lights in the lower foreground. Probably the co-pilot has seen some weaker parts of the light phenomenon where the captain possibly has seen the somewhat brighter parts only. The longer duration and the wider view of the light reflection against the sky by Mr. van Uden could be explained very well in this perception.

I discussed these facts with both pilots and Mr. de Poorter suggested that the sight of his co-pilot could be a bit better too, purely looking at the age of each person. Mr. De Poorter retired as pilot just a week ago (Nov 2008), his co pilot is some 20 years younger.

With these remarks I will end this second eyewitness report. I have told both pilots that this extra information also will be sent to the Minor Planet Center and to some other people who have asked for the information.

Jacob Kuiper

My thanks to Monty Robson from the John J. McCarthy Observatory, (himself a recently retired airline pilot and responsible for some of the last observations of 2008 TC₃ before it entered the atmosphere) for contacting Jacob Kuiper and for providing explanation of some of the aviation terms in the accounts.