There has been lots of questions about my wingsuit BASE jump from Lord Berkeley’s seat. I thought I would try and answer some of the technical questions in this article.
Requirements for a wingsuit jump:
There are four things you need for a wingsuit exit to be viable:
- Initial vertical drop
- Terrain to fly over
- Total altitude
- Landing
- Initial vertical drop. This is the vertical part of the cliff that you need for the suit to inflate and pressurize in order to gain forward momentum. The shorter the drop the less time you have to get the suit flying. The point of impact on this jump was less then 100m below.
- Terrain to fly over. Once the suit is pressurised and you start flying forward you need terrain that is at a lesser gradient to which your wingsuit can fly. The steeper the terrain is, the more separation from it you gain, increasing your margin for error.
- Total altitude from exit to landing. The total height of most jumps in the alps are around 1000m and although wingsuit jumps from 300m have been done, it’s hardly a flight. This flight was 500m total altitude covered. I flew for 30 seconds and had 50 seconds under canopy before I landed.
- Landing. Some jumps just aren’t possible because there are no landing options. The more technical the landing the more time you want under canopy in order to correct any malfunctions and set up your landing.
This is why it is so hard to find a wingsuit exit in the UK. We are limited when trying to find these four variables. As one variable becomes more marginal you look for a bigger margin in another. This jump was so technical because of the small margin in all areas.
The jump
The red line on the graph shows the terrain profile. I used a laser range finder and picked six points on the line of least resistance. The numbers are in metres and show horizontal vs vertical:
20-105
39-123
71-147
117-193
178-249
321-372
The blue line shows my flight on the day. Thermals and a slight headwind helped with my performance. I recorded all my previous flights and compared them to the terrain profile to make sure I would make the flight under all different types of conditions. Some margins were less then others but all previous jumps would have been successful on this exit. The most important part of training to me was consistency with exits. Visualisation is also key. On easier jumps I would pick a point that was the same value as this jump and use it as a reference for how close I would be to the rock.
(c) Hamish Frost
Access
Excellent to learn about this. Thanks and well done 🙂 Ill be back on this site