New Delhi — Late last week a Soviet military plane touched down at Kabul airport, carrying more than 100 severely wounded soldiers of the beleaguered Afghan regime. The casualties are from a battlefield in Paktia province south of Afghanistan's capital. They are the largest number brought to Kabul from a single mission during the past two years, according to Western embassies.
The thrust by the Soviet Red Army in Paktia, along with the armed forces of the Babrak Karmal regime, is but one of several large-scale offensives against the guerrillas, which began early this spring.
It was in some respects as predictable as the melting of the snows. But, in others, it was unusual. The Soviets, according to Western diplomatic reports from Kabul, are fanning out in three key areas in battalion-regimental strength; they are using unprecedented numbers of fighter-bombers and helicopter gunships to support their ground attacks; and they no longer appear interested in ''winning the hearts and minds of the people of Afghanistan.''
There are also reportedly subtle differences inside the capital of Kabul. According to a third world parliamentarian, who attended last week's celebrations on the fifth anniversary of Afghanistan's first pro-Soviet Marxist regime, there was no evidence during daylight hours of Soviet military presence on Kabul streets.
Likewise, the head of the Soviet delegation to the celebrations, Uzbek party chief Sharaf Rashidov, led a small, low-key delegation. The largest delegation was from East Germany and was, like Rashidov's, remarkably conciliatory during the gala round of receptions and dinners. It was as if, according to the visitor , ''there was no war going on. There was only its aftermath in the Geneva peace talks.''
Such comportment, according to Western officials, seems to indicate a new Soviet ''carrot and stick'' approach. It would also appear that the Red Army - with its 105,000-man occupying force - is intent on inflicting the maximum number of casualties on Afghanistan's mujahideen before the next round of UN-sponsored peace talks, set for Geneva in June.
A major offensive against Afghanistan's third-largest city, Herat, near the Iranian frontier, began April 15 and reportedly is still going on. According to Western reports from Kabul, the bombing of Herat - a city of 100,000 and a guerrilla stronghold - was extended last week from the northwestern suburbs into the entire northern part of town. Civilian casualties are said to be extensive. According to a resistance source based in Peshawar, about 2,000 people have been killed.
Intense fighting was also reported in the town of Ghazni, between Kabul and the southern city of Kandahar. In Kandahar itself mujahideen have reportedly held up a column of critically needed Kabul-bound petroleum tankers for at least 15 days, as fighting in that city goes on. There has also reportedly been extensive bombardment in the Shomali district, between Kabul and the Hindu Kush mountain range.
But the mujahideen keep striking back, and have reportedly seen the emergence of a new group of local commanders since fighting slackened at the beginning of last winter. In Paktia province - which, from the beginning, has been one of the hardest for the Afghan regime to control - local forces have reportedly held off the Red Army in a 15-day attack. The rebels are believed to be establishing a stronghold in the mountainous terrain, which they are using as a key training center and staging area for attack.