Twenty Seven Mile Ridge

61.147709, -145.735960
Updated March 31, 2024

Description

The first time I went to Thompson Pass to fly Twenty Seven Mile ridge, a group of us drove right past it thinking there's no ridge around here big enough to soar.  Finding nothing bigger down the road, we returned and set up camp in the parking lot across the road at the toe of the ridge.  The next two days proved that it doesn't take much of a slope to have a lot of fun soaring. 

Twenty Seven Mile Ridge is located at the top of Thompson Pass on the West side of the road.  The large field at the base of the ridge is a dense alder jungle swamp in the summer which makes this a winter only flying site.

Snowmobiles are not required to access the launch but they definitely make it easier.

Weather Considerations

  • A light flow out of the North is what you want.  Be prepared not to fly.  Bring your skis, traction kite, speed wing, snowmobiles, or whatever you can think of doing if the winds aren't right at the ridge.
  • Primarily a ridge soaring site, with a north wind.  Normal precautions regarding watching the wind speed apply, to avoid getting blown over the back into the Power Lines.
  • Recommended wind limitations are

Requirements

This site is not managed by the Arctic Air Walkers.

P3 is the recommended pilot level, and it may not be suitable for P2 pilots.  This site is not managed by the Arctic Air Walkers and there are no specific requirements to fly here aside from strong launching skills and good judgment.  Pilots should have P3 skills, but because it is a remote site, with greater consequences for messing up, pilots should follow the USHPA recommended operating limitations for P2 pilots, which are:

  •  Maximum base wind of 12 mph. 
  • Maximum peak gusts to 15 mph.
  • Maximum gust rate of 5 mph in 5 seconds
  • Should not fly in thermal lift where peak climb rates exceed 200 fpm (not likely to be an issue since this is a low height hill that is flown in the winter/spring).
  • Launch from slopes steeper than 4:1 with the wind within 25 degrees of being straight up the slope.

Hazards

The obvious hazard is the large high tension power lines routed directly behind launch.  Other than that, this is a pretty straightforward ridge soaring site.

Below are some other hazards that are common to sites everywhere:

  • Keep spectators a safe distance away when launching.  A distance of 50 feet forward and 30 degrees either side of center of anticipated take off course and 30 feet rearward of starting point target is the recommended clearances.
  • Keep spectators safe by choosing flight paths that are no closer than 50 feet from spectators.
  • Light aircraft operate everywhere in Alaska.  It's your responsibility to maintain visual awareness as required to see and avoid other traffic.  Paragliders and hang gliders present a narrow profile to other traffic.  Wingovers or spirals are a good way to signal your presence when aircraft are approaching.
  • Avoid landing closer to powerlines towers and other obstacles than necessary.  The recommended minimum clearance from powerlines is 100ft.



WARNING: The descriptions of typical flying conditions listed in this Site Guide reflect the experience of the authors of the guide. The conditions that you encounter at the site may differ, sometimes substantially, from those described. These descriptions may not be relevant to the possible experience of any other pilot, particularly one who is relatively inexperienced or new to the Site.