1 Air Algérie 5017 in VIIRS 24 July 2014 Scott Lindstrom, William Straka III 1
Background Air Algérie 5017 departed Ouagadougou, Burkina Faso, to Algiers, Algeria at 0107am Contact lost at rougly 0155Z Wreckage of the plane had been found in the Gossi region of Mali, 50 kilometres (31 mi) north of the border with Burkina Faso. This was confirmed by both the French and Burkina Faso military The cause of crash is currently under investigation VIIRS overflew the Gossi, Mali region at roughly 0155Z, about the time of the crash. – The DNB observed an emitted light source near the source of the crash.
Executive Summary An investigation, using both VIIRS imagery as well as other sources was undertaken to determine the source of the light Sources include – VIIRS DNB, M13 and I04 Bands – Media reports along with VIIRS imagery Media reports include written as well as video from French military drone over crash site
VIIRS DNB 24 July, Z Gossi Gao
VIIRS I05 (11 m) 24 July, Z
VIIRS IMAGERY Air Algérie
VIIRS Imagery To determine whether or not this was a static source or the crash itself, two methods were used 1.VIIRS DNB imagery 2.VIIRS DNB + IR imagery Method 1 - VIIRS DNB imagery – Data from the surrounding clear sky nights were used to see if point source existed before hand – 21 July 2014 used, since the region was covered by convection on 22 and 23 July 2014 during VIIRS nighttime over passes – Red circle indicates location of emissive light source
VIIRS DNB 21 July, Z Gossi Gao
VIIRS DNB 24 July, Z Gossi Gao
VIIRS DNB 24 July, Z Gossi Gao Gossi Gao
VIIRS Imagery Method 2 - VIIRS DNB + IR imagery – The 3.9 m band is used for fire detection, so the resulting fire might possibly provide a thermal signature – The image was zoomed to look at the light source directly – Two channels were used: M13 and I04. M13 is more sensitive to fires, but I04 provides greater spatial resolution – Orange arrow indicates center of light source in DNB
VIIRS DNB 24 July, Z
VIIRS M13 24 July, Z Lack of IR signature
VIIRS I04 24 July, Z Relative hot spot in I04 imagery
VIIRS Imagery Summary Both methods indicate this is a source only on 24 July VIIRS DNB imagery Source only present on 24 July 2014 imagery and not on 21 or 25 July VIIRS DNB + IR imagery The M13 (3.9 m) imagery showed no thermal hot/warm spot at the location of the light source. This is likely due to cloud cover (hence the diffuse nature of the light source) The I04 (3.7 m) imagery did show a relatively warm (274.5K) spot in the exact location of the light source, indicating a possible fire of some sort. However, it was quite small (~2 pixels) However, this alone does not prove it is the location of the crash. Hence independent sources must be used
MEDIA REPORTS + VIIRS IMAGERY Air Algérie
Executive Summary Media reports place the crash to the south of Gossi, Mali, roughly 50 kilometres (31 mi) north of the Burkina Faso border The online version of the Wall Street Journal provided footage from the French military drone which first located the crash
French Military Drone footage The drone coordinates are: 15 o 8.149’ N, 1 o 4.755’ W ( N, W). These coordinates seem to verify those from other sources. We can place these coordinates on to the VIIRS imagery.
VIIRS DNB 24 July, Z 15 N 1 W N, W
VIIRS I04 24 July, Z 15 N 1 W N, W
Media reports +VIIRS Imagery Summary Media reports place the crash to the south of Gossi, Mali, roughly 50 kilometres (31 mi) north of the Burkina Faso border, the approximate location of the light source The online version of the Wall Street Journal provided footage from the French military drone which first located the crash The coordinates of from the French military drone ( N, W) place the source of the Air Algérie 5017 crash site
CONCLUSIONS Air Algérie
Conclusions The VIIRS overpass at ~0155Z on 24 July indicates an anomalous light source in the vicinity of the Air Algérie 5017 crash site, roughly at the time contact was lost Using multiple methods, including coordinates from the French military drone which located the crash, it is almost certain that the anomalous light source is from the fire resulting from the impact of Air Algérie 5017 in southern Mali.