Clifton suspension bridge.
I have wanted to jump off the Clifton Suspension Bridge
since I was 18 years old, but always considered this an irational urge.
Falling off sea cliffs in 2006, whilst deep water soloing, made me realise
that it is entirely possible to jump off the clifton suspension bridge without
injury in the right conditions and correct manner.
A 75m fall into 12m of water at spring high tide is completely survivable.
I will aim for a 40m fall by the end of 2008 in both fresh and salty waters.
I will regularly swim under the clifton suspension bridge to master the tidal river.
I will throw things off the clifton suspension bridge and time their descent.
- 28/08/2008 - conker, 6 seconds.
I will actively research the reactions of the clifton suspension bridge management,
local media and rescue authorities to attempts to jump off the bridge.
Experience of distress in the Avon Gorge suggests that within 10 minutes several
fire, ambulance and police units will be in attendance. After 15-20
minutes the Portishead life boat and several coastguard units would also
I prefer to make the jump naked, but am considering carrying a float on a 15m
line for rescue.
Jumps from the clifton suspension bridge are never reported in the media to avoid inspiring
other potential jumpers.
55 m/s (about 125 miles per hour) arms legs spread
Feet first with arms clasped tight against their side, can achieve terminal
velocities over 90 m/s (200 miles per hour).
It is estimated that the human body reaches 99% of its low-level terminal
velocity after falling 573m 1880ft which takes 13-14 sec. This is 117-125mph
at normal atmospheric pressure and in a random posture.
The speed of a diver from a 30 metre cliff is estimated to be only about 90
km per hour. This is only one-third or so of the terminal velocity.
There is a trick people do for diving very high heights. Drop a fairly heavy
object before you to break the surface tension. Could also jump into the
wake of a pasing boat.
A prime example of the latter was a 17-year-old male who in 1979 leaped off
the Golden Gate Bridge from a height of 250 feet. According to one report,
"he recount[ed] a slowing of time initially, and mid-fall, when fully
realising the oncoming impact, strove to adjust his attitude to the vertical
feet-first position. An almost perfect entry was achieved. Although dazed, he
swam to shore" and checked into a hospital, where his worst injury turned out
to be several cracked vertebrae.
The Golden Gate Bridge is said to be the most popular suicide location in the
world--at least 1,200 people had jumped as of 2003, of whom fewer than 20
survived. A more typical outcome was that of a stuntman calling himself Kid
Courage, who jumped off the bridge in 1980 trying to set a free-fall record.
He landed flat on his back and was dead when pulled from the water with
massive internal injuries.
The key to survival appears to be vertical entry. The 17-year-old male
survivor said he may have touched bottom, perhaps 20 to 25 feet down--plenty
of room to disperse the force of impact. In contrast, Kid Courage's body
never sank beneath the surface, meaning he'd gone from 75 mph (a Golden Gate
leaper's peak speed) to zero in maybe six inches.
Jumpers who hit the water do so at about seventy-five miles an hour and with
a force of fifteen thousand pounds per square inch.
May 8, 1885, a 22 year old woman called Sarah Ann Henley survived a jump from
the clifton suspension bridge when her billowing skirts acted as a parachute,
and subsequently lived into her eighties.
According to the clifton suspension bridge tour guide someone survived a fall
within the past 15 years. All records should be with coroner.
245 ft (75 m) above high water level.