BRS developing a chute for very light turbofans

 - January 9, 2008, 3:59 AM

Ballistic Recovery Systems (BRS) of St. Paul, Minn., has received a $600,000 grant from NASA to develop a whole-airplane parachute system for very light jets. The company has identified eight aircraft in various stages of development that could become a market for the product and has agreements to work with three possible manufacturers of jets in the 5,000- to 8,000-lb-mtow, 350-kt-cruise-speed category.

In its preliminary design phase, the system is envisioned in a two-stage format. A separate drogue chute would deploy first to slow the aircraft down to around 175 kt, and a main, Kevlar-reinforced chute would then lower the aircraft to the ground slowly enough to protect its occupants from injury.

BRS v-p Dan Johnson told AIN that his company is also considering developing the first-stage parachute as a separate product that could be installed without the main canopy and used as either a conventional drag chute on landing or a “return to control” chute for situations in flight where an aircraft may encounter an unrecoverable spin or otherwise lose aerodynamic control. He said aircraft up to the size of airliners could use such a system from BRS.

Asked about the projected weight of a full, two-stage system on a very light jet, Johnson said that roughly 2.5 percent of mtow–at 80 lb, the operative figure in the Cirrus piston models–is a number that seems to keep surfacing in hypothetical calculations. That would translate to 125 lb for a 5,000-lb aircraft and 200 lb for an 8,000-lb aircraft. Asked about price, he said it’s far too early in the program to commit, but a “wild guess” would be $30,000 to $50,000 per aircraft.

BRS developed the Cirrus airframe parachute system (CAPS) that spared the life of Texas pilot Lionel Morrison when his four-place Cirrus SR22 lost an aileron in flight last fall. CAPS is standard on Cirrus SR20s and SR22s, and a similar BRS system is available for retrofit on Cessna 172s. BRS started making whole-airplane parachute systems for ultralights and claims 156 “saves” (lives preserved) over its 21-year history. The company said it has more than 500 of its parachutes installed on certified aircraft, with an overall total of more than 17,000 parachute systems delivered worldwide.

For the jet system, the drogue chute would begin by slowing the airplane and stabilizing it. The pilot would have the option of deploying only the first chute if necessary. Under more extreme conditions, however, the second chute would then take over and lower the aircraft to safety. One complication could be where to stow the parachute package so as not to compromise a jet’s pressure vessel. Johnson said the system would not need to ride within the pressure vessel, but conceded that beefing up the structure could present design challenges.

The grant from NASA is the third for BRS under the agency’s small business innovation research (SBIR) program. BRS received $70,000 from NASA in 1994 and then $600,000 to develop “new, lightweight and strong materials that would allow a parachute to deploy at the speeds required for high-performance, general aviation, single-engine airplanes.” The second grant led to the certification of the Cirrus system.

BRS’ Johnson said the company has letters of intent with VisionAire for its single-turbofan Vantage project and has a cooperative agreement with Cirrus for a possible turbofan being explored by that Duluth, Minn.- based company. Johnson declined to identify a third company with which BRS has signed an LOI. Johnson said the company is targeting the developmental Cessna Citation Mustang for the new product, though it has not opened discussions with Cessna, yet. At press time BRS had a meeting scheduled with Adam Aircraft concerning its A700 very light jet.

He added that some developmental single-engine jets were among the very light designs being considered for BRS systems. He also said Dr. Sam Williams, head of Williams International, had stipulated to some of those single-engine candidates that he would consider selling Williams engines to them only if they incorporated a BRS parachute in their design plans.