Meteorology
'Hannibal' had encountered strong headwinds as CW196 on 26 Feb. The weather recorded on 1 March is described as "not unusual , with surface winds of 10 to 20 mph, southwest to west". (12) This is consistent with the estimates of ground speed from the radio log. Modern understanding of meteorology in the region suggests this to be normal. Where this record was made is to be determined. It seems consistent with Sharjah and local variations encountered enroute may have been different.
Other conditions may be encountered as
follows.
Generally winds in the Gulf region blow
NW to SE as a result of a stationary high pressure cell over the
Arabian peninsula and a low pressure cell over the Zagros mountains
of Persia. This is affected seasonally by the Indian monsoon.
Associated with these winds is the
Shamal (north) or dust storm. Even if the winds are
insignificant on a particular day any dust raised by previous
wind events will remain in the atmosphere for extended periods.
Predominantly a Summer occurrence Shamals are recorded earlier in
the year.
"Most of the Eastern Emirates escape this as the wind funnels the dust and sand into the Empty Quarter. There are occasions, though, when the High Cell over Saudi Arabia and the Zagros Lee Low extends over a majority of the UAE and dust haze is brought over the entire region for a short time. When the cells migrate back to their normal positions the winds rapidly decrease; then the haze remains in situ and the strong thermal heating causes (the dust haze) to linger in a blanket over the country for days at a time, with visibilities remaining at around 5000 to 3000 m for most of the time, reducing to below 1500 m on occasions." Dust haze can be observed to altitudes of 12000ft. (22) Dust plumes are observed extending over the Gulf of Oman also.
Sea and land breezes are the main
circulations in the Arabian Gulf that affect the meteorology of the
region. They develop due to strong heating of the land and weak
large scale winds. 23)
"Although fog is most common in winter months it is not unknown
during the 'spring' or early 'autumn'. This type is advection fog,
when air of high dew point over the sea is carried over the cooler
land. As the moist air moves landwards, it is forced to rise over
the denser desert air. Such blankets of fog may penetrate inland for
many miles." 24) This fog
has been observed as very dense (less than 50m visibility) but
usually has 'burned" off by mid morning. Wind and daytime
heating remove the effect but wind alone may not disperse fog. The
northern coast of Oman is not affected as a consequence of the
prevailing wind.
The effect of warm moist air impacting
the Hajar Mountains of the Musandam Peninsula is known to cause
convection cloud formation that can lead to violent thunderstorms
over the area. These do not always produce rainfall but would
cause a significant hazard to aviation. Electrical activity
may affect radio performance.
Assuming the aircraft landed in the sea
and was able to float or otherwise launch buoyant craft, any search
of the area would need to understand the currents and movements of
the Gulf of Oman. Understood in recent times are counterclockwise
circulating surface currents moving at around 1.5mph. (0.7m/s)
As will be noted these effects are
generally more significant to the west of the Hajar mountains. 'Hannibal' was due to transit from the east coast of the Hajar
mountains to Sharjah between 12.05 and 13.35.
Of interest are the instructions from
the "Air Route Book" issued to Imperial pilots. 'Leaving
Sharjah the track strikes east across undulating light coloured
desert. In bad visibility aircraft should commence to climb as 70
miles ahead mountains 20 miles to the north of the track rise
abruptly to 6000ft.. The desert changes to red sand and darker sand
crossed by the courses of waterways before the mountains are
crossed. In doubtful visibility no attempt should be made to cross
at less than 8000ft. The track crosses the coast just north of a
very distinctive well mapped bay. Every effort must be made to check
ground speed in order to ensure an accurate ETA for land fall on the
Persian coast.' 25)
A description of flying in the
Musandam noted, "This was often in rough conditions when
there were thunderstorms, or downdrafts and curlovers as strong
winds tumbled over the mountains." (41)
A description of the meteorological hazards of flying from a correspondent who was based at Sharjah flying Blenheims. (1943)
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Richard Hobby, 2002 - 8. ( This page is a collation of information from various sources, please address any concerns about source and accreditation to page author )