Report on Langila (Papua New Guinea) — February 1997
Bulletin of the Global Volcanism Network, vol. 22, no. 2 (February 1997)
Managing Editor: Richard Wunderman.
Langila (Papua New Guinea) Eruptions to about 11-km altitude create aviation risks
Please cite this report as:
Global Volcanism Program, 1997. Report on Langila (Papua New Guinea). In: Wunderman, R (ed.), Bulletin of the Global Volcanism Network, 22:2. Smithsonian Institution. http://dx.doi.org/10.5479/si.GVP.BGVN199702-252010.
Papua New Guinea
5.525°S, 148.42°E; summit elev. 1330 m
All times are local (unless otherwise noted)
Crater 3 remained quiet during February, but Crater 2 continued to generate Vulcanian explosions; in some cases ash columns rose to 6 km. During early February observers noted loud detonations, roaring, and rumbling. About mid-month bad weather obscured the volcano. From 21 February until the end of the month the explosions seemed weaker. During February there was no seismic recording.
Aviation sources reported ash plumes on 11-12 February (BGVN 22:01) to at least 10.5 km altitude. Since then, Tom Casadevall learned of an aircraft encounter with an ash cloud that was presumably from Langila. The commercial 747 was en route on R-204 from Seoul to Brisbane. The encounter, 1129 GMT on 12 February, occurred at an altitude of ~11 km (37,000 feet) at a location [~550 km SSW of Langila, near 8.75°S, 144.5°E]. The aviator's observations follow.
"Outside air temp[erature] was at -48°C, suddenly [outside air temperature] increased to - 38°C. Smell of sulfur was experienced in the cockpit. No change in engine parameters. Crew attempted to contact [air traffic control] to change course, but were unable to make radio connection due to poor signal. After 5 minutes, flight exited dust cloud and continued on to Brisbane. Safe and uneventful landing. Upon aircraft return to Seoul, all engines were inspected per [Airline Maintenance Manual] for volcanic ash ingestion. Inspection reports found no evidence of problems."
Volcanic ash plumes pose hazards to aircraft; for example, the ash, which is not discriminated from weather clouds by on-aircraft instruments, can seriously damage jet engines.
Geologic Background. Langila, one of the most active volcanoes of New Britain, consists of a group of four small overlapping composite basaltic-andesitic cones on the lower eastern flank of the extinct Talawe volcano. Talawe is the highest volcano in the Cape Gloucester area of NW New Britain. A rectangular, 2.5-km-long crater is breached widely to the SE; Langila volcano was constructed NE of the breached crater of Talawe. An extensive lava field reaches the coast on the north and NE sides of Langila. Frequent mild-to-moderate explosive eruptions, sometimes accompanied by lava flows, have been recorded since the 19th century from three active craters at the summit of Langila. The youngest and smallest crater (no. 3 crater) was formed in 1960 and has a diameter of 150 m.
Information Contacts: B. Talai, H. Patia, D. Lolok, P. de Saint Ours, and C. McKee, RVO; Geoff Garden, Bureau of Meteorology, Australia; Thomas J. Casadevall, USGS.