Cliff diving is an extreme sport that requires highly-trained athletes to jump from a cliff into the water below. However, unlike many other extreme activities, cliff divers must first train at lower heights before they even consider jumping higher.
Recently, a daredevil posted GoPro video footage of their base jump that went terribly wrong. The jumper crashed into the side of the cliff and fell to earth below.
Definition
Cliff strike is an unfortunate term for when something goes terribly wrong during a BASE jump spliff (an acronym for jump and spliff). Typically involving high speed jumps off of cliffs, it’s defined as an accident involving one or more people that could result in serious bodily injury. Usually there’s video documentation of the event to remember it by.
Cliff jumping may not always be the safest or most fun option, but it sure can be exciting. Base jumpers have long reported near misses in terms of accidents or injuries while jumping off a cliff, but there are a few tricks of the trade to prevent one of these scares from occurring. Most importantly, always wear a helmet when jumping from a cliff – otherwise, you could end up paralyzed or unable to breathe.
History
On D-Day morning, Lieutenant Colonel Rudder (Commanding Officer of the 2d Ranger Battalion, which would become known as Ranger Infantry Battalions) and Lieutenant General Max Schneider (Commanding Officer of the 5th Ranger Battalion) devised a plan to eliminate enemy positions atop Pointe du Hoc. Force A, composed of Rangers from that battalion, landed near Pointe du Hoc with orders to eliminate an observation post and guns located along its western cliff edge.
After landing, Force A soldiers separated into small groups that would take off for their assigned objectives. Utilizing mortar flares and predetermined radio signals, the Rangers would signal to Ranger infantry battalions that they had made a successful landing and were now starting their ascent to the top.
As the Rangers of Force A began their ascent, they were joined by ladder-equipped DUKWs that helped them reach the top. Additionally, ropes attached to cliff faces provided extra assistance as the Rangers gripped onto them during their climb.
The Germans were able to cut through many of these ropes, but some clung on and allowed the Rangers to scale the cliff face. Since it wasn’t particularly high up, they were able to reach the top in a relatively short amount of time.
In the weeks prior to D-Day, the Rangers had been honing their cliff climbing techniques on various cliffs throughout England and on the Isle of Wight. These skills proved essential for them when they needed them most on D-Day; they needed to climb quickly in order to destroy gun positions and observation posts atop Pointe du Hoc before it was too late.
Techniques
There are various methods used to prevent cliff strikes. These include re-vegetation, cliff reshaping and profiling.
Re-vegetation is the most commonly applied technique, particularly on slopes with high soil mobility, since this type of vegetation can grip the soil and slow down movement. On more stable slopes, however, re-vegetation may also be combined with reshaping measures to reduce erosion risk.
Another technique involves re-engineering the slope by altering its angle and decreasing cliff heights. Unfortunately, this method has some drawbacks: it cannot be used effectively when facing steep rocks that are very high; additionally, it’s costly and takes time to implement.
Reshaping is an additional method that can be utilized as a precaution against rock falls, but it must be accompanied by warning signs and safety measures like blocking off paths or restricting access to hazardous areas.
Furthermore, re-engineering should be undertaken promptly to reduce the likelihood of rockfall before it occurs. This is especially crucial in coastal areas where waves may be particularly powerful during stormy conditions.
Geological and geophysical experiments can also be employed to characterize fracturing and identify vulnerable parts of a cliff. Ground penetrating radar (GPR) is often employed on the surface of cliffs to provide high resolution data, though its penetration depth may be limited due to weathering effects.
To carry out this experiment, four vertical GPR scans (P1, P2, P3 and P4) were directly performed on the cliff face at two separate locations (figure 3). These scans were made with a RAMAC system and 100 MHz unshielded antennae which provide an ideal compromise between resolution and penetration in these types of limestone rocks.
All four profiles reveal a major fracture (F2) dipping inward towards the mass at approximately 25 meters away, which was not visible during the initial geological and geophysical investigation on site. This fracture is clearly visible in all GPR tomograms taken.
These investigations reveal that the massif fracturing system consists of two primary families: Fa striking N20 degE+-10deg and Fb striking N130 degE+-10deg. This fracture system exhibits a vertical dip of around 90deg+-15deg and contains multiple fracture planes along plateau outcrops.
Safety
At times of cliff strikes, several safety measures should be taken. These include wearing safety helmets, using a good harness and securely fastening your body in place. These precautions help prevent slips while in flight and guarantee a secure landing.
Cliffed coasts present many risks, such as marine and subaerial weathering and erosion; tectonic movements; land subsidence; hydrological factors; and activities like fossil hunting. All of these can contribute to cliff falls or other related incidents.
The most obvious danger is that, if you aren’t careful, you could easily slip off the cliff and end up in the water below. This could prove fatal or at least extremely hazardous.
Other geological hazards presented by cliffs are more subtle and often less noticeable. For instance, while a falling stone may not seem like much of an issue at first glance, its sheer force of impact can cause severe injury.
One of the most frequent geological accidents occurs when someone trips over a rock and plunges into the water below, leading to serious injuries. This could range from minor scrapes and bruises to major head trauma or even death.
A responsible geological field trip leader will take all necessary precautions to guarantee the safety of his students or visitors. This includes checking tides, weather and cliff conditions before embarking on their excursion. Furthermore, they should be on alert for potentially hazardous cliffs that appear unprotected.
To minimize the likelihood of such an accident, plan your fieldwork carefully and visit the area during low tide or dry weather. Additionally, move quickly away from any rocky outcrops or cliffs to reduce the chance of being caught by a fall.
When working near or on a cliff, wearing a safety helmet is the most important precaution to take. This is especially true if working in rockfall-prone formations such as shale, clay or limestone where rockfall risks are high. Furthermore, wearing the hat helps shield your eyes from sunlight damage and potential blinding effects from ultraviolet rays.
