Safety Investigation Report 2018:1 Factual Information/1.7/1.7.2
SAFETY INVESTIGATION REPORT MH370 (9M-MRO)
1.7.2 Comments on the Information Available
- 1) Forecast Charts
- a) Significant Weather Chart
The Significant Weather Chart (SIGWX) PGCE05 EGRR 061800 issued by World Area Forecast Centre (WAFC) London Fixed Time Prognostic Chart ICAO Area G SIGWX for FL250-630 (25,000 ft to 63,000 ft above standard sea-level pressure) valid 1800 UTC, 07 March 2014 [0200 MYT, 08 March 2014] showed that the filed flight plan route (red dotted line - Figure. 1.7E [below]) passed through a westerly jet stream with wind speed of up to 150 kt at latitude 30°N at FL390. Another westerly jet stream with wind speed of up to 100 kt at FL310 at the destination. Light clear air turbulence (CAT) might be expected from 25°N onwards to the destination. However, no significant adverse weather phenomenon was expected for the whole planned flight route.
Figure 1.7E - Significant Weather Chart PGCE05 Issued by WAFC London Fixed Time ICAO Area G Prognostic Chart SIGWX FL250-630 valid 1800 UTC, 07 March 2014 [0200 MYT, 08 March 2014
Source: WAFC London
- b) Wind and Temperature Forecast Chart
The wind and temperature forecast chart PWGE25 for FL340 valid 1800 UTC, 07 March 2014 issued by WAFC Washington showed the jet stream as in the significant weather chart above. The forecast winds at the last civil radar point and last air defence radar point were below 20 kt (Figure 1.7F [below]).
Figure 1.7F - The wind and temperature forecast chart PWGE25 issued by WAFC Washington for FL340 valid 1800 UTC 07 March 2014 [0200 MYT, 08 March 2014]
Source: WAFC Washington
- a) Significant Weather Chart
- 2) Significant Meteorological Information
Significant Meteorological Information (SIGMET) 3 was issued for the GUANGZHOU FIR valid from 12:45 to 16:45 UTC, 07 March 2014 [0200 MYT, 08 March 2014] indicated a thunderstorm forecast north of latitude 27°N and moving eastwards at 50 km/h in the layer with cloud tops at FL260.
- 3) Volcanic Ash Advisory
Volcanic ash advisories issued by Darwin Volcanic Ash Advisory Centre (VAAC) on 07 March 2014 at 06:27 and 18:37 UTC [2045 MYT, 07 March 2014 and 0045 MYT, 08 March 2014] for Sinabung (Sumatra, Indonesia) highlighted volcanic eruption located at 3.10°N 98.23°E (Figure 1.7E [above]) and volcanic ash plume observed up to FL120 and the plume was extending toward the west.