Selecting a Break Off Altitude
by Tom Buchanan, S&TA

Defining a Break Off Altitude

An accident or injury is often the result of a chain of events, and one of those elements can be the break off phase of the skydive.  Break off is designed to give each jumper adequate space to open without the threat of a collision, and it should lead to an opening altitude that gives each jumper plenty of time to deal with a malfunction.   Selection of a break off altitude is dependent on many factors and should be carefully considered when planning each skydive.  While break off altitudes of about 3,500 feet were common many years ago, contemporary skydivers are frequently choosing higher break off altitudes to improve safety.  How to establish those break off altitudes has become a concern for some jumpers, and is worthy of discussion.

Minimum opening altitudes are easy to define.  USPA Basic Safety Requirements (BSR's) require us to initiate main deployment no lower than 3,000 feet for "A" license holders, 2,500 feet for "B" license holders, and 2,000 feet for "C" and "D" license holders.  USPA also expects us to make the decision to cutaway no lower than 1,800 feet.  Those altitudes are minimums, and should often be increased.

Many contemporary parachutes are designed for staged openings that can take 800 - 1,000 feet between initial deployment and a fully functioning parachute.   In order to make a decision to cutaway by 1,800 feet, a jumper with a normally slow opening parachute may actually need to begin deployment by 2,500 - 3,000 feet, regardless of experience or license held.

Not only are many parachutes now designed to open a bit slower, but when malfunctions happen, they can be more radical, and will generally spin or descend faster than malfunctions on older style canopies.  This faster malfunction descent rate also requires an upward adjustment in initial opening altitude in order to provide the jumper with enough time to handle the emergency.

Old School vs. New School

'Back in the day' it was considered macho to break off well below 3,500 feet, and to initiate deployment at 2,000 feet or even lower.  That may have been fine in the golden days of skydiving, but contemporary canopy designs that deliver longer standard deployments, or faster malfunction descent rates, have driven many jumpers to increase initial opening altitudes to 3,000 or 3,500 feet, and sometimes higher.  In fact, these higher than historically standard opening altitudes are a good idea for any jumpers with high performance or slow opening parachutes.

Break off altitudes allow us to move away from each other, and then to begin deployment at a sufficient altitude to allow for main parachute evaluation and cutaways.  Since break off altitudes are based at least in part on intended opening altitudes, we can see that increasing opening altitudes to compensate for new parachute designs and greater safety margins, will also push break off altitudes higher.

New parachute designs not only tend to open slower and present faster descending malfunctions, but even when they don't malfunction, contemporary elliptical designs can frequently surge forward, or spin off heading very quickly.  These undesirable opening characteristics must be anticipated, and extra separation needs to be established to prevent collisions through the deployment process.  The extra separation required by high performance parachutes demands that we break off formations high enough to allow adequate tracking time to achieve the needed distance.

The 'Tween Time

The altitude needed between break off and opening will depend on many factors including the size of the group and freefall speed.  Large groups obviously need more time to gain separation, and groups with extreme freefall speeds, such as those encountered in freeflying, need time to slow down for a safe deployment.  Jumpers should also consider the opening characteristics of each parachute in the group, and allow extra time for separation if there are any canopies that may open off heading or in a rapid forward surge.  The USPA Skydivers Information Manual (SIM) recommends that break off altitudes be established at least 1,500 feet above the highest intended opening altitude for groups of five or fewer, and at least 2,000 feet above the highest intended opening altitude for groups of six or more.  These altitudes can of course be increased for very large groups, when some of the jumpers are inexperienced or not current, or when the nature of the jump dictates a higher altitude.  A jumper who has slowed to a standard belly to earth freefall position will travel about 1,000 vertical feet every 5.5 - 6 seconds, but a jumper in a track will often have a faster descent rate.  Thus, the recommended minimum break off of 2,000 feet above opening altitude allows only about 10 -12 seconds for a jumper to recognize the break off command, turn, track away, slow down, wave off, and then begin deployment.

Since many jumpers are now using high performance parachutes with radical opening characteristics, we should expect initial deployment altitudes to be in the neighborhood of 3,000 feet, and in general, that does seem to be where many of us are beginning deployment.  Adding USPA recommended vertical break off distances of 1,500 - 2,000 feet brings the typical recommended break off altitude to 4,500 (small groups) or 5,000 feet (groups of six or more).  Freeflyers may choose even higher break off altitudes to allow them to slow down to safe opening speeds.

Not all jumpers will choose to use the USPA recommended altitudes, but every group must be careful not to limit the options available to individual jumpers.  Often a jumper who wishes to open at 3,000 feet and wants to use the USPA suggested break off altitudes will be uncomfortable voicing a concern in the group setting, so we should all be willing to stick by the USPA standard unless there is a compelling reason to select lower break off or opening altitudes.

In Review

	Minimum opening altitudes need to be selected that will compensate for contemporary parachute characteristics.  These opening altitudes may be higher than those recommend in USPA BSR's.  Normal main parachute opening altitudes will often be about 3,000 feet, even for experienced jumpers.
	Break off altitudes need to be established that allow for adequate separation, and they need to be adjusted for the unexpected opening characteristics of contemporary canopies.   USPA recommends break off altitudes be 1,500 - 2,000 feet above the highest intended opening altitude.
	Skydivers are frequently uncomfortable asking for higher opening or break off altitudes, so group organizers should select altitudes that serve everybody's anticipated needs, and should encourage higher break off altitudes when conditions warrant them.

- Tom Buchanan S&TA