Soaring in thermals often involves multiple gliders (a "gaggle") sharing a single thermal. As such, rules and "thermalling etiquette" have been established to minimize conflicts and potential collisions. **Remember: SAFETY, NOT EFFICIENCY, IS MOST IMPORTANT!**
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## Rules
### Everyone circles in the same direction
- the first glider in the thermal establishes the direction of turn
- any glider that joins the thermal must circle in the established direction
### Even spacing between gliders at similar altitudes
- 2 gliders should circle opposite to one another
- 3 gliders should form a triangle, 4 a square, and so on...
- use extreme caution when circling with more than 3 gliders, as the [[Glider Visual Scanning and Collision Avoidance#Blind Spots]], especially the rear blind spot, are likely to be occupied by another glider
### Do not fly directly above or below another glider
- most gliders have [[Glider Visual Scanning and Collision Avoidance#Blind Spots]] directly below the cockpit; high-wing designs will also have a blind spot above and to the side of the cockpit
### Do not turn inside another glider
- turning inside ("showing your belly") another glider involves both aircraft in each other's [[Glider Visual Scanning and Collision Avoidance#Blind Spots]]
### Do not establish a thermal near an existing thermal
- attempting to use a new thermal in close proximity to an established thermal involves converging traffic from both circles
### If an unsafe condition exists - LEAVE
- this includes: too many gliders have joined, you have lost sight of a nearby glider, someone else is flying unsafely, etc
- LOOK and exit the thermal in the safest way possible
## Techniques
### Entry
- join at thermalling speed; do NOT abruptly pull up to decelerate!
- aim wide of the thermal, maneuvering in to join when the proper spacing exists
![[GFH entering thermal.png]]
### Maintaining spacing
- gliders with different performance may be sharing the same thermal
- maintain proper spacing by varying airspeed and [[Radius of Turn]]; slower gliders will fly a tighter circle, faster gliders will fly a wider circle
- rear visibility is most restricted; the glider behind another glider should make corrections to maintain proper spacing
## Additional Resources
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