N4677VCessna 172RG · 1980

On April 29, 2013 about 1401 Pacific daylight time, two airplanes, a Cessna 172RG, N4677V (172RG), and a Cessna 172M, N64030 (172M), collided in midair approximately 3 miles southwest of Calabasas, California. The 172RG certified flight instructor and the commercial pilot sustained minor injuries, and the pilot rated passenger sustained serious injuries; the airplane sustained substantial damage to the left wing. The 172RG was registered to AmeriFlyers of Florida, LLC, and operated by American Flyers as a 14 Code of Federal Regulations (CFR) Part 91 instructional flight. The 172M commercial pilot and private pilot were fatally injured, and the airplane was destroyed. The 172M was registered to a private party, and operated by the commercial pilot under the provisions of 14 CFR Part 91 as a personal flight. Visual meteorological conditions prevailed, and no flight plan was filed for either flight. The 172M departed from the Santa Monica Municipal Airport (SMO), Santa Monica, California about 1313, and the 172RG departed from SMO about 1353.

The certified flight instructor (CFI) from the 172RG reported that the purpose of the flight was to familiarize two pilot rated students (one of which was seated in the back seat) with the local airspace and normal practice areas. The CFI stated that, after departing SMO they flew north along the Santa Monica shoreline before proceeding to the Malibu State Park and the Simi Valley practice area. The CFI stated that, as they crossed over Topanga Canyon, they switched from the SMO tower frequency to the local practice area frequency and made the first position report transmitting "Malibu and Simi Valley practice area, white Cessna, over Topanga Canyon, northbound at 2,800 climbing 3,500". They leveled off at 3,500 feet and the CFI asked the pilot in the right seat to perform the cruise checklist. The CFI stated that they made a second radio call transmitting, "Malibu and Simi Valley practice area, white Cessna, over Calabasas, south of the 101, east of Malibu Canyon Road heading west towards Westlake 3,500." The CFI stated that no airplanes acknowledged their position reports nor did any other airplanes transmit a nearby position.

The pilot under instruction then conducted a right clearing turn from a westerly heading to a northerly heading and then brought the airplane back to the left and leveled off on the original westerly heading. The CFI reported that he was looking to the front and the left in his normal traffic scan practice. When the airplane had leveled off, he heard a "loud bang" and felt something hit the airplane on the left side. He looked outside at the left wing and noticed that the inboard leading edge was damaged from the wing root outboard, the pitot tube was missing and the left wing strut was bent. The pilot's side window was also broken and metal was protruding into the airplane. The CFI took control of the airplane and, unable to maintain altitude, executed a forced gear up landing onto a golf course. The airplane slid about 430 feet when the left wing impacted a tree that spun the airplane about 180 degrees before it came to a rest.

A witness reported that he and his wife were walking in the area when they heard an extremely loud strike. He looked up and saw an airplane descending almost vertically to the ground before it went out of his view; he did not note hearing an engine noise. Shortly after, he saw a plume of dark smoke rise from where the airplane had disappeared. The witness further reported that his wife observed a second airplane depart the area to the west.

Review of the radar data revealed that the  Cessna 172RG was observed on radar immediately after departure from SMO at 13:51:32 until shortly after the collision occurred. At 14:01:04, the airplane's transponder return showed 3,500 feet mean sea level (msl) with a westerly track and a ground speed of 104 knots. At about 14:01:14 the track indicated the start of a gradual right 6 degree turn towards the northwest at a ground speed of 103 knots. At about 14:01:46 the airplane maintained a heading of 266 degrees until the collision occurred at 14:01:55 at 3,400 feet msl (about 2,540 feet above the ground). After the collision, the airplane's track continued to the north followed by a left turn towards the west and a right turn to the northwest. The last radar return was at 14:02:32 at an altitude of 2,800 feet msl.

At 13:58:23 the Cessna 172M is identified on radar cruising in an easterly direction at 3,200 feet msl at 110 knots. At 13:59:00 the transponder return indicated the airplane was at 3,200 feet msl and the track showed the start of a gradual left turn at 111 knots.  At 14:01:09 the airplane was at 3300 feet msl, and at 14:01:28 the airplane was at 3400 feet msl flying at 100 knots. The collision occurred at 14:01:55. The airplane track made a sharp left turn and descended rapidly into terrain.

Cessna 172RG Flight Crew

The CFI, age 37, held an airline transport pilot certificate for airplane single- and multi- engine land issued December 22, 2012. The CFI also held a flight instructor certificate for airplane single- and multi-engine land, which was issued February 19, 2012. His second-class airman medical certificate was issued on May 11, 2012 with no limitations. The CFI had a total of 2,200 total flight hours, 600 of which were in the accident airplane make and model.

The pilot under instruction, age 34, held a commercial pilot certificate for airplane single- and multi- engine land issued on January 20, 2013. The second pilot's first-class airman medical certificate was issued on November 20, 2012 with the limitation that he must wear corrective lenses. The second pilot reported 485 total flight hours; the accident flight was his first flight in the accident airplane make and model.

Cessna 172M Flight Crew

The first pilot, age 69, held a commercial pilot certificate for airplane single-engine land issued on October 29, 2003. The pilot also held a flight instructor certificate for airplane single-engine land which was issued on July 25, 2011. The pilot's third-class airman medical certificate was issued on March 5, 2012, with the limitation that she must wear corrective lenses. The pilot's logbook was not located. On the pilot's application for her most recent medical examination she reported 1,750 total flight hours, 50 of which occurred within the six months preceding the examination.

The second pilot, age 63, held a private pilot certificate for airplane single-engine land issued May 10, 2010, and a certified airframe and powerplant mechanic certificate issued on February 18, 2010. The pilot's third-class airman medical certificate was issued on December 6, 2011 with no limitations. On the pilot's application for his most recent medical examination he reported 1,350 total flight hours, 25 of which occurred within the six months preceding the examination.

Cessna 172RG

The Cessna 172RG, serial number 172RG0224, was manufactured in 1980, and was a four seat, high wing airplane that was predominately white in color with blue striping. The airplane was powered by a Lycoming O-360 series, 180 horsepower engine, and was equipped with a 2 blade McCauley propeller. The airplane was registered to Ameriflyers of Florida LLC, and operated by American Flyers. The airplane's most recent maintenance was a 100 hour inspection that occurred on April 5, 2013 at an airframe total time of 10,383.

Recovery personnel reported that during the recovery, about 43 gallons of fuel was removed from the fuel tanks.

Cessna 172M

The Cessna 172M, serial number 17264976, was manufactured in 1975, and was a four seat, high wing airplane that was predominately white in color with red and blue striping. The airplane was powered by a Lycoming O-320 series, 180 horsepower engine, and was equipped with a 2 blade McCauley propeller. The airplane was registered to a private individual and operated by the commercial pilot. Review of the maintenance records indicated that on April 16, 2013, at an airframe total time of 5,862.3 hours, the airplane's engine and propeller were reinstalled onto the airplane from a previous incident involving a propeller strike. The airplane's most recent annual inspection also occurred that day.

The nearest weather reporting station was located about 9 nautical miles northeast of the accident site at the Van Nuys Airport (VNY), Van Nuys, California. At 1351, VNY reported clear skies, wind 140 degrees at 6 knots, visibility 10 statute miles, temperature 17 degrees C, dewpoint 11 degrees C, and an altimeter setting 29.82 inches of mercury.

Cessna 172RG

The Cessna 172RG, serial number 172RG0224, was manufactured in 1980, and was a four seat, high wing airplane that was predominately white in color with blue striping. The airplane was powered by a Lycoming O-360 series, 180 horsepower engine, and was equipped with a 2 blade McCauley propeller. The airplane was registered to Ameriflyers of Florida LLC, and operated by American Flyers. The airplane's most recent maintenance was a 100 hour inspection that occurred on April 5, 2013 at an airframe total time of 10,383.

Recovery personnel reported that during the recovery, about 43 gallons of fuel was removed from the fuel tanks.

Cessna 172M

The Cessna 172M, serial number 17264976, was manufactured in 1975, and was a four seat, high wing airplane that was predominately white in color with red and blue striping. The airplane was powered by a Lycoming O-320 series, 180 horsepower engine, and was equipped with a 2 blade McCauley propeller. The airplane was registered to a private individual and operated by the commercial pilot. Review of the maintenance records indicated that on April 16, 2013, at an airframe total time of 5,862.3 hours, the airplane's engine and propeller were reinstalled onto the airplane from a previous incident involving a propeller strike. The airplane's most recent annual inspection also occurred that day.

Cessna 172RG

The airplane landed onto the golf course hard and dug into the fairway grass. The grass and concrete showed sliding marks for about 430 feet along a bearing of about 73 degrees magnetic, followed by a tree, and then the main wreckage. The main wreckage was orientated from tail to nose on a bearing of 253 degrees magnetic.

The airplane's left wing leading edge sustained two large indentations. One indentation was located at the wing root and was approximately three feet long. Within the damaged wing root were distinct white and red diagonal paint transfer marks that were at about a 50 degree angle when compared to the nearest longitudinal rivet line. The outboard dent was located about 2.5 feet from the wing tip and was about three feet long. Within the dent were brownish red scrape marks as well as tree residue imbedded in the dent. The left strut sustained a dent approximately 2 feet from the bottom of the left wing. One of the propeller blades had a one inch gouge along the leading edge about 6 inches from the propeller tip. The left side door posts were bent aft, and the upper portion of the back center window post was bent to the right.  The empennage remained intact and mostly undamaged.

About four pieces of right horizontal stabilizer and elevator with red and blue striping from the Cessna 172M were found on the ground resting near the left horizontal stabilizer of the 172RG. Scratch marks were noted along the upper outboard portion of the largest horizontal stabilizer piece. These scratch marks were measured to be at about a 50 degree angle when compared to the nearest longitudinal rivet line.

Cessna 172M

The wreckage of the 172M was located at an elevation of 1,170 feet on a mountain side about 5 miles southeast of Westlake Village, California.

The airplane impacted the ground in a nose low attitude and a postimpact fire ensued; the wreckage was heavily burned and no paint transfers or obvious scratches from the collision were noted. The engine was separated from its engine mounts and the propeller was separated from the engine. The airframe sustained forward accordion crushing throughout. The flap actuator was located and the flaps were in the up position. The flight control cables were traced throughout the airframe and control continuity was established from the cabin controls to their respective flight control surfaces. The right horizontal stabilizer and the elevator were separated from the forward horizontal stabilizer spar about 6 inches from the spar root. A small portion, which was believed to be the inboard portion of the right horizontal stabilizer, was found within the wreckage. The remaining components of the right horizontal stabilizer and elevator were not present on scene, however, they were found on scene with the 172RG.

Postaccident examination of the engine from the 172M revealed heavy thermal discoloration throughout. The cylinder rocker covers were removed; the valves were intact and sustained thermal discoloration. The right magneto was separated from the engine, and the left magneto remained attached. The ignition leads were consumed by fire. The spark plugs were removed and exhibited wear consistent with "Worn Out – Normal" when compared to the Champion AV-27 check-a-plug chart. When viewed from the spark plug holes, the interior surfaces of the cylinders and piston heads revealed no signs of internal catastrophic damage.

Cockpit Visibility

According to a Cessna representative, a left seated male with an average eye level height looking out the front windscreen has about 85 degrees visibility from the center of his view to the right and 52 degrees from his center of view to the left. The pilot also has about 53 degrees of visibility from the center of vision downward when looking out the left side window and 22 degrees from the center of vision downward when looking from the right window.

Other

FAA Regulations [14 CFR 91.113(b)] required that each person operating an aircraft maintain vigilance so as to "see and avoid other aircraft."

The Federal Aviation Administration (FAA) reported that at 1313, the 172M pilot contacted Santa Monica air traffic control tower and requested to stay in the pattern following maintenance. At 1340, the pilot requested a departure to the west. The controller approved the request, and terminated services.

At 1353, the 172RG pilot requested clearance to depart SMO to the west to follow the shoreline northbound. The request was approved and shortly thereafter services were terminated.

There was no evidence of the two airplanes communicating with each other.

The autopsies of the pilots from the Cessna 172M were performed by the Los Angeles County Department of Coroner, Los Angeles, California.

The first pilot's autopsy was conducted on May 1, 2013, and concluded that the cause of death was multiple traumatic injuries.  Specimens from the autopsy were sent to the FAA's Civil Aerospace Medical Institute (CAMI) in Oklahoma City, Oklahoma, and toxicological tests were performed. The results were negative for ethanol and drugs in the pilot's liver or muscle; tests for carbon monoxide and cyanide were not performed.

The second pilot's autopsy was conducted on May 2, 2013, and concluded that the cause of death was multiple traumatic injuries.  Specimens from the autopsy were sent to the FAA's CAMI and toxicological tests were performed. The results were negative for ethanol and drugs in the pilot's liver or muscle; tests for carbon monoxide and cyanide were not performed.

Evaluating the paint transfer marks on the 172RG wing root and the 172M horizontal stabilizer components, along with the radar provided ground speed of both aircraft, it was possible to calculate the horizontal convergence angles and the collision angle between both airplanes. The airplanes converged at about a 50 degree angle relative to their longitudinal axes. The 172RG was traveling at about 102 knots, and the 172M was traveling at about 101 knots. Based on these values the collision angle between the two airplanes was determined to be 80 degrees relative to the horizontal plane.