From the Archives: The Terrible Truth About Wire Strikes

[Music] the rugged mountains and lush meadows of California it's an idyllic setting for many it's the American dream and for pilots the freedom to see this beautiful country from the air is the reason we learn to fly in the first place but while we're enjoying all this beauty we just might forget there are wires down here wires are a necessary part of modern life and though there are a hazard at times we can't live without them they carry most of our telephone conversations and they transmit our electrical power in short they're indispensable pilots have to learn to live with wires but it's not always easy recently a working group of several California utilities and representatives from the aviation industry decided to address the issue head-on after a three-year research and feasibility study the group reached a consensus on both a wire marking program and the pilot education efforts to help prevent air craft wire strikes this video is one part of the wire strike prevention program [Music] at one time or another we've probably all had a closer encounter with wires than we would have liked some closer than others in an average year some 115 pilots fly into wires of one kind or another back in 1989 a student pilot and his instructor earned national press coverage when they flew their Cessna into power lines near Ontario California neither pilot was hurt in the accident but the airplane was definitely a little worse for wear more recently both pilots were killed when this helicopter lost its rotor to wires in the Cahuenga Pass north of Los Angeles contrary to what you might think wire strikes are a bigger problem than they seem between the beginning of 1986 and the end of 1990 FAA and NTSB records suggest there were some 584 wire strike accidents on file for civil aircraft alone this doesn't count in military strikes or unreported wire collisions the latter evidenced by power company reports of literally thousands of broken wires unaccompanied by a crumpled aircraft comparing reported wire strikes with actual downed wires suggests that only about 10% are reported it might seem that wire strikes are the greatest threat from tall obstacles such as this 820 foot radio tower near Fullerton Airport in Fullerton California in fact though at least 70% of all wire strike accidents occur at or below 100 feet AGL location rather than height would seem to be the more important determinant of a wire strike hazard another common misconception about wire strikes is that the pilots involved are all low time amateurs not so in fact studies of past accidents suggest just the opposite most pilots who run into wires are experienced aviators [Music] more than half of all strike victims have 1,000 hours or more logged and the largest group of rotary wing aviators involved are in the 10,000 hours and up group similarly the misconception is that wire strikes only occur during buzzing or other unauthorized low-level maneuvers though the more level passes you see here were legal and performed for the video program wonderful world of flying wire strikes don't normally result from buzzing accident statistics suggest legal flight operations such as crop dusting police surveillance and medevac generate many strikes pilots who do strike wires can expect the FAA to aggressively pursue an F AR violation though it's true helicopters do operate at low level more than fixed wings wire strikes don't always happen to the other guy fixed-wing aircraft are among the most common offenders in fact airplanes account for four times more accidents than do helicopters fully 75% of all these aircraft fixed and rotary wing are destroyed or severely damaged in wire collisions finally you might logically expect weather to be a factor in wire strike accidents [Music] as it turns out logic isn't always correct studies suggest visibility is typically more than three miles and sky conditions are clear to scattered when aircraft collide with wires the good weather applies equally to a fixed and rotary wing accidents so apparently bad weather doesn't often force pilots down some pilots believe wire strikes could be avoided altogether if all wires were marked or buried but that's obviously a very expensive and impractical solution and no guarantee that marked wires will be seen as in the Cahuenga Pass incident which wires to mark is the problem wires that airports such as this one near Sacramento California are obvious choices and that's a key as to where to place warning devices such as these orange balls wire location and visibility are more important marking criterion than height or span strikes are less likely at some locations such as this TV transmitter farm on the top of a mountain but even towers that are relatively easy to spot may have supporting wires that are nearly invisible though as the study revealed the illegal flight operations aren't often a cause of wire strikes FAA r91 1:19 specifies minimum altitudes for both fixed-wing and rotary-wing operation the Reg states no aircraft may operate below 1,000 feet AGL over a congested area and 500 feet over an uncongested area helicopters may operate at lower levels provided they can make a successful emergency landing in the event of a power failure depicting all wires graphically on charts is no guarantee of solving the problem though there's a little question a review of charts prior to a low-level flight is an excellent idea not all wires are depicted on charts however ironically none are shown below 200 feet in height where a statistics show that most wire strikes occur so even careful pre-flight scrutiny of available reference material before level mission what protects you against a strike merely knowing that wires are nearby isn't any guarantee of safety in some 40% of recorded collisions pilots who collided with wires knew they were near but still collided with them often because they were distracted a high recon pass is always a good policy before a low-level run or landing ideally a ground director can help keep an aircraft clear of obstacles but that's a luxury that's not always available unprepared landing sites can include hazards that may be almost impossible to spot from the air one possible reason that fixed wings clip wires four times more often than helicopters may be simply speed helicopters typically operate at lower air speeds and can even stop in midair if necessary to avoid a wire strike a helicopter patrolling at 40 knots requires only 1/3 the distance to turn and avoid compared to a fixed-wing aircraft flying at 80 knots in addition a pilot flying slower can fly closer to the wires before initiating corrective action allowing him more time to spot the wires themselves or the support structure on either side distance is a key factor a pilot is 10 times more likely to spot wires at a horizontal distance of 800 feet than at 2,400 feet for both types of aircraft a pull-up is a more efficient avoidance maneuver than a turn both fixed wings and helicopters can modify their flight path quicker with a pull-up than a turn there are several visual techniques that can help in this see and avoid requirement nature rarely creates straight lines and such lines can alert a pilot to the presence of wires ahead especially in the vicinity of highways canals railroad tracks and other man-made routes pilots who fly low-level regularly make it a habit to scan left and right through a full 90 degrees to look for the origination point of wires another visual cue that many experienced pilots use once they spot a wire is to fly with reference to the vertical support structure rather than the wire itself wires may be oxidized or corroded so there's virtually no reflection to attract the eye they may blend well with the background under certain light conditions making them almost impossible to see finally pilots operating in a crew environment should announce any wire they spot so other crew members can help maintain proper separation all crew members should remember they're in a wire environment whenever the aircraft is operated below a Ridgeline if you do have a close encounter with a wire and wish to alert others to the hazard report the problem to the FAA and also to NASA with the aviation safety reporting system if your mission requires frequent operation at low level consider installing a wire strike protection system several companies offer such systems for both fixed-wing and rotary-wing aircraft these systems are intended to slice wires apart before they can bring an aircraft down if you'll be required to fly low reduce fuel load to maximize climb performance in case you spot a wire avoid operation at or near max gross weight finally schedule a low-level mission so you won't have to look into a bright rising or Setting Sun that further obscures the wires in review of this wire strike prevention program at least 70% of all wire strike accidents occur at or below 100 feet AGL most pilots that hit wires are experienced aviators more than 50% have over 1,000 hours wire strikes do not normally result from buzzing however regardless of the reason FAA will investigate a wire strike mishap and enforcement action is likely 75% of wire strike accidents result in substantial weather is not a primary cause of most wire strike mishaps here are some other points to remember consult aeronautical and other charts before flying low level perform a high-altitude recon pass before all low-level flights use a ground guide or communicate with ground personnel regarding wires before flying low or landing at a remote site reduce your airspeed when flying in a wire environment normally a pull-up is more effective than a sharp turn in avoiding wires fly over the supporting structure not the wire span and finally look for supporting structures not the wire except for takeoff and landing most of us will never have a legitimate reason to operate our aircraft at the extreme low levels where wire strikes are most common but for those pilots who do the message is clear wires are a hazard we have to learn to live with and that means giving them the widest berth possible [Music] we're rock [Applause] [Music]

Channel: Air Safety Institute

Views: 131,885

Keywords: institute, aopa, aviation, pilot, fly, flying, flight, plane, airplane, airport, air, safety, asi, air safety, training, education, aircraft, owners, pilots, association, archive, vintage, wire, strikes, helicopter, student, truth, bill, cox, journalist, power, lines, hazards, crop, dusting, eletric, telephone, phone, low, altitude, maneuvering, agl, cutter, faa, far, 91, vfr, utility, california, retro, old, vhs

Id: MKdUfrUWNJs

Length: 13min 36sec (816 seconds)

Published: Mon May 04 2020