Time is precious. Why spend half your vacation time in an airport waiting for flight connections? Instead, go for direct flights to get on the slopes faster. Here's OnTheSnow's top picks for where you can ski a few big name resorts in the West by catching direct flights from San Francisco Airport (SFO).

The shortest amount of flight time combined with the shortest drive or shuttle time can start the ski vacation fast at Mammoth Mountain Ski Area. Mammoth lobbed onto the list most recently with new direct flights added for this winter, starting Dec. 16. United Airlines with nonstop flights operated by Sky West hops daily from San Francisco over the Sierras in about 90 minutes to Mammoth Lakes-Yosemite Airport (MMH). No need to rent a car, as the ski area sits 15 minutes from the airport with most hotels offering shuttles.

Two direct flights leap daily from SFO to Aspen Airport (ASE) in about two hours and 15 minutes each. Downtown Aspen sits three miles from the airport and Snowmass Village five miles away. Car rentals aren't needed as shuttles are available to hotels, and a free skier shuttle service runs between Aspen/Snowmass, Aspen Highlands, and Buttermilk.

The 2.5-hour direct link from San Francisco to Vancouver International Airport (YVR) in British Columbia makes Whistler Blackcomb an easy destination, too. Air Canada operates three direct flights daily, and United Airlines runs four flights daily, two of them operated by Sky West. The airport sits two hours from the ski resort, accessed via the improved Sea-to-Sky Highway revamped for the Olympics. Pacific Coach's Whistler SkyLynx provides a bus service to Whistler.

Direct flights of less than three hours connect SFO with Calgary International Airport (YCC), making the Banff ski areas easy to reach. Air Canada runs one direct flight per day, and United Airlines operated by Sky West flies three times each way daily. Frequent airport transfer services by reservations are available between the airport and Banff hotels. The ride from Calgary to Banff takes less than two hours, but you can often leave the driving to someone else by catching shuttles. Ski Big 3 tri-area lift tickets and bus service between Banff and the ski slopes simplifies logistics for accessing Sunshine Village, Lake Louise Ski Area, and Mount Norquay.

More information: United Airlines, Air Canada, Ski Big 3 Tickets, Whistler SkyLynx.