Russia may hike air sorties to 300 a day

For a moment, the deafening roar of a jet engine drowns out the shrieks of joy from children splashing in the warm waters of the Mediterranean.

Another Russia warplane is taking off from Latakia airport, in northern Syria – proof of the growing involvement by President Vladimir Putin in what he calls a ‘‘war on terrorism’’ and his critics denounce as merely an attempt to prop up his ally, President Bashar al-Assad, by attacking pro-western insurgents rather than the fanatics of Isis.

After a military build-up dating back several weeks, Russia now has about 50 aircraft in Syria.

Yet an unexpected calm hangs over the airport, which was recently closed to international civilian flights to make room for the Russian forces.

The Kremlin says it is flying an average of about 50 missions a day in Syria, although the number, coordinated with Assad’s ground forces, varies from day to day.

Sources close to the operation say the aim is eventually to raise that to 200-300 a day, marking a considerable escalation. As part of preparations, a new airstrip is reported to be under construction nearby.

Russia, using the conflict to showcase its military prowess, has deployed Su-24M and Su-34 fighterbombers, low-flying ground attack Su-25CM jets and multi-role Su-30CM fighters. They are backed by Mil Mi-24 attack helicopters and multi-role Mi-8 helicopters.

Military analysts said the first airstrikes, which began on September 30, were aimed at probing rebel forces, establishing their positions and the extent of their firepower.

By attacking simultaneously on several fronts, Assad and his allies hope to deprive insurgents of the ability to move forces in the defence of a particular front, keeping them bogged down and overstretched. The Kremlin claims its operation is directed purely against Isis and Jabhat al-Nusra , al Qaeda’s branch in Syria, and its affiliates.

The West says much of Russia’s firepower has been directed against US-backed moderate rebels from the Free Syrian Army – and civilians.

The Russian airstrikes coincide with fresh attacks by the Syrian army on rebel groups that have wrested much of the country from Assad’s control since the start of the bloody civil war four years ago.

In Latakia the atmosphere seems strangely cheery and the war far away. Inside the base, Russian pilots or workers jog in shorts in the heat of the day.

‘‘They take their jogging as religiously as we take our sheeshas [hookahs],’’ said one local. ‘‘Maybe we will convert them to sheesha sessions and they’ll convert us to jogging.’’