Parachute or No Parachute?
Having a "reserve" parachute is generally mandatory for sky diving. It is also recommended for paragliding and paramotoring.
Emergency parachutes for airplanes are becoming more popular. There is an interesting history. First, you must learn about a man named Jim Hanbury, a skydiver, hang glider, base jumper, and stunt man who became interested in parachutes for ultralights. In 1977, Jim Hanbury took a Quicksilver Sprint ultralight up and cut the wires supporting one wing, placing the ultralight into a a spinning free fall. He actually had the event filmed with a video produced. Once in free fall, he cast a reserve parachute in the same manner as used for skydiving (except it was mounted to the ultralight and not to the pilot) and the plane crash landed, without injury to the pilot. He later tested a similar concept, except he used a rocket to ballistically launch the parachute with a rocket. (Hanbury later died testing a ballistic parachute for a Cessna 150--the lines became entangled with the plane's tail.) Throwing the parachute resulted in slower deployment, where the ballistic deployment was fast enough function when deployed with less than 100 foot of altitude. Others developed the concept further.
Here is a video showing a two seat Quicksilver E-LSA Trainer with footage showing Hanbury's testing.
Today, ballistic parachutes are available from BRS and Stratos (Magnum). Stratos began in 1990 in the Czech Republic. BRS began in 1980 in Minnesota, as a result of a hang glider accident suffered by the founder Boris Popov. BRS was actually granted a US Patent: https://patents.google.com/patent/US4607814 A US Patent for an airplane parachute was granted in 1919--so emergency parachutes have been contemplated for a long time. Popov and Hanbury no doubt knew of each other.
With the advent of UAV drones, there are many examples of saving the UAV using reserve parachutes--the leader being Fruity Chutes with remote ballistic launchers from SkyCat and Harrier.
There is no doubt that these devices do save lives. Success is recorded in video footage for Cirrus and some aerobatic planes. Deploying the device with a front mounted "tractor" propeller seems to work well. Deployment from an ultralight with a high mounted pusher is a bit more problematic as there is risk of entanglement in the prop. To deal with this, most installations shoot the rocket out the side (Aerolite horizontally, Quicksilver out and upward with the bridle routed around the rear bracing and up the wing toward the center anchorage. Hopefully, the prop has stopped, and the ultralight has slowed sufficiently that the bridle avoids getting entangled in the tail or the prop . (Success on the Quicksilver with floats is shown in the above video.)
These devices seem valuable, but one must carefully weigh risk vs reward. Unexpected deployment in flight is a remote possibility. Pulling the chute eliminates pilot control and avoidance of dangerous obstacles, like power lines, during the drifting descent. They probably are effective at 200 foot altitude, but only if the pilot reacts fast enough. (The 2018 Quicksilver crash in Maryland was equipped with a chute but it was not pulled.) My search has not produced any video evidence of successful deployment in an Aerolite 103 with a soft pack and a horizontally sideways launched rocket. However, at least two reports exists of successful deployment in an Aerolite. The horizontal launch is recommended by Stratos (in their manual) on the side where "the propellers blades move in the
upward direction" a to use the effect of prop wash to move the chute upward away from the rudder and elevator and, if the bridle did impact the prop, the drop would tend to drive it upward. (Steel or Kevlar is recommended for the bridle for any length that might impact the prop.) Reasoning is that a vertical launch may allow the momentum of the plane to fly below and in front of the chute, causing the plane to fly up considerably and introduce a significant swinging oscillation. Actually, the manual recommends from zero to 45 degrees up angle---the way the system is recommended for the Quicksilver with a cannister.
The “factory” install on the Aerolite shoots the rocket out the side horizontally with the bridle nylon zip tied to the rear of the wing. The zip ties hopefully break during deployment or at least after the rocket has fully extended the chute lines and the chute begins to fill (rocket thrust is around 70 pounds and most zip ties break at 50 pounds) with the bridle traveling around outside of rear strut to the center anchoring point on top of the wing in front of the engine. Hopefully the bridle stays in front of prop and avoids a prop strike, but if on the upward side of prop rotation, the bridle would likely be deflected upward.
I did find one first hand "testimony" of a crash a Dragonfly ultralight with a "pusher" engine. Note that the BRS is mounted in front of the wing with the rocket pointed upward. It deployed and did not entangle with the prop even though the pilot failed to kill the engine.
The green Aerolite crash into trees in Maine was with a parachute. The yellow Aerolite crash into a pool enclosure in Florida was without a parachute although it was equipped with one. Often you see or hear of planes equipped with chutes but pilots did not engage them. Both planes heavily damaged—both pilots walked away!
The “ideal" reaction to an engine out is to land safely without a parachute. Parachutes should only be used if the pilot has lost control of the plane and control cannot be immediately re-established for stable flight. Invariably, the plane will be dropping like a projectile. (Broken wings, locked/jammed elevator, rudder or aileron. Fortunately, these types of failures, while notorious, are not as common as many fear and risk can be minimized with good maintenance, and sound flying judgment.) With a chute, the airframe will be heavily damaged--maybe beyond repair. And very good possibility of a prop strike, putting a ? on the engine's condition. A successful emergency landing in a field will likely only require minor repairs. Fly always with a healthy anticipation of the need to land safely without warning. The story of the red Kolb shown below in a cornfield:
"The 590th landing, I bent a landing gear leg. I took off from I22 and climbed to about 750 feet agl when the engine dropped to an idle. A split connector for the throttle cable had come unscrewed. I was too low to return to the airport so I elected for a crosswind landing in a cornfield that was close to a house and a main road. |
I landed with the cornrows. It did not seem like I hit that hard but the up wind landing gear (right) leg was bent back and up about 4 to 6 inches. There was no damage to the tail feathers." |
Hay, wheat and even soybean fields are the most desirable for emergency landings--corn fields can be less forgiving, but always better than trees, overhead wires or fences. Be prepared to compensate the farmer for crop damage. Be careful in pastures as livestock don't stand still. Roads are a possibility, but traffic and overhead wires often become a hazard. Practice landings with engine at idle and a steep descent so as to learn the best configuration to land over obstacles with a very short field. Properly flown, the Aerolite can land, over a 50 ft obstacle in only 300 feet (100 yards).
The most compelling justification for a chute is a structural failure or damaged control system. In other words when the plane is no longer flyable. Aerobatic pilots wear chutes and “bail” when the plane’s structure fails or they lose control with no hope of regaining control. Usually they have 1000’ AGL for the chute to open. The whole plane ballistic chutes may work when deployed as low as 200’ AGL.
There are three types of containers used for ballistic parachute--cannister (see Dragonfly above and Zigolo below)---vertical launch (See Dragonfly below) and soft-pack. See Aerolite 103 below. The soft pack is considerably lighter than the 24 pounds allowed by the FAA in Part 103.
Choice of parachute location may be affected by CG weight and balance.
Another Option
Aerobatic and glider pilots have been wearing emergency parachutes for years. In fact, aerobatic pilots and passengers are required to wear them when performing aerobatic maneuvers. They "bail out" if/when the plane is no longer flyable. Wings coming off, unrecoverable spins, loss of elevator or rudder control are reasons to use the chute. If the plane is unable to fly, whether it be a ballistic parachute or a emergency parachute for the pilot, it is time to use the parachute.
I believe that there are advantages for the ballistic for the plane as it probably deploys faster and there is less loss of altitude during deployment. With an emergency parachute, the pilot must first exit and get clear of the plane. This can be a major issue at low altitude. Unhooking set belts, and moving your body to a safe exit could easily take 2-3 seconds versus pulling a handle---the difference is a loss of 200-300 feet or more.
What is often underestimated is the descent rate with the parachute deployed. In a perfect scenario, the plane will descend in a stable horizontal attitude and land on it's wheels, impacting at about 10-15 mph. If it is swinging, the impact could be much harder. In many instances, such as a wing failure, the plane would not land in a stable horizontal attitude. In any case, the impact will probably result in total destruction of the airframe and it is possible that parts of the airframe may strike and injure the pilot. And, the pilot will be subjected to high compression forces in the spinal column and neck. If the plane descends nose first, leg/foot injuries are highly possible. Finally, the pilot is still strapped in at impact, with the possibility of a fire from the fuel stored and fuel lines directly behind the pilot.
There are risks associated with ballistic systems. Inadvertent/accidental activation being one.
Bailing out has another set of risks. As mentioned, more altitude is required. The biggest advantage is the pilot is clear of the plane--no risk of fire or being struck by airplane parts. The pilot is likely to impact the ground at the same 10-15 mph. But, proper body positioning and use of leg muscles will likely result in less injury to the spine and neck. Even so, for an older pilot, a parachute "landing" is likely to sustain some form of back injury unless he is in extraordinary physical condition--about the same as jumping off an 8 foot step ladder. Another advantage is the risk of inadvertent "launch" of the rocket and parachute is nil.
Normally, an emergency pilot parachute would only be effective if bailing out about 500'AGL. (Ballistic chutes maybe above 300') But, here is the testimony of a Christen Eagle aerobatic pilot: "My partner told me later he figures I got out at about 100 feet. I thought he was wrong, due to his maybe being excited, and hanging from his own chute, and being far away, and since I wasn't dead. When I brought my chute to a guy who has a great reputation as a rigger, he figured it was somewhere between 100-200 feet." This pilot did not get the full benefit of the chute--and probably impacted the ground at >20mph=30ft/sec but he did survive and walked away.
It should also be remembered that the "original" parachute use by an ultralight pilot (Handbury) was a "hand thrown" reserve parachute---the kind now used by paramotor "ultralights". Tandem versions are available rated for 210kg=462lbs or about the same for an ultralight plane with a 208 lb pilot.
US Patent 4445654-Inventor Handbury, 1982
"An ultralight aircraft and/or pilot recovery system includes a parachute having a canopy connected by means of a plurality of shroud lines to a first elongated cable having a length to position the parachute clear of the aircraft engine and propeller with a second cable for connecting the parachute to the frame of the aircraft and including a harness worn by the pilot which includes a pouch for containing the canopy folded within an inner pouch to permit the pilot to grasp and toss the chute clear of the aircraft for deployment for recovery of the aircraft. An alternate embodiment provides for connecting the parachute to the harness worn by the pilot and securing the harness to the aircraft to thereby give the pilot the option to recover the aircraft or cut loose from the aircraft for pilot recovery only."
As a footnote...Handbury died in 1986 while testing a parachute for a Cessna 150. The parachute became entangled in the plane's tail and control was lost at an altitude of 3000 feet. Handbury, wearing an emergency parachute bailed out at about 400 ft above the ground, but there was insufficient time for the chute to open.
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