NTSB Identification: CHI00MA066A
HISTORY OF FLIGHT
On February 8, 2000, about 1504 central standard time, a Moravan Z242L, N5ZA, and a Cessna 172P, N99063, collided in flight over a residential area of Zion, Illinois, approximately 2 miles from the approach end of runway 23 at the Waukegan Regional Airport (UGN), Waukegan, Illinois. N5ZA impacted the roof of a hospital, and N99063 came to rest on a residential street after striking a tree and a sidewalk. Both airplanes were destroyed on impact. The pilot and passenger on board N5ZA were fatally injured. The student pilot of N99063 was also fatally injured. Both airplanes were operating under the provisions of 14 Code of Federal Regulations (CFR) Part 91 without flight plans. Daytime visual meteorological conditions prevailed at the time of the accident. N5ZA's cross-country flight originated at Sheboygan, Wisconsin, at 1400.
At 1338:34, the pilot of N99063 contacted the UGN air traffic control tower (UGN ATCT). The pilot reported that she was 7 miles south of the airport, confirmed having the automatic terminal information service information, and requested permission to perform practice takeoffs and landings. At 1342:18, the UGN ATCT local controller (LC) cleared N99063 for touch and go, and instructed the pilot to make a right hand traffic pattern. Over the next 45 minutes, the pilot of N99063 operated in the closed traffic pattern and performed nine practice takeoffs and landings. At 1426:26, the pilot of N99063 requested clearance for the option and performed a full stop landing.
At 1455:25, the pilot of N5ZA made his initial call to UGN ATCT. Approximately 6 seconds later, the pilot reported that he was 15 miles northeast of the airport. The LC acknowledged the call and asked the pilot, "are you coming down the shoreline?" The pilot responded, "That's affirmative." (Radar data provided by the Federal Aviation Administration [FAA] from its Chicago terminal radar approach control [TRACON], which covers the traffic pattern altitude at UGN, showed that N5ZA was 4.5 miles east of the shoreline). The LC instructed the pilot to "report turning final at the shoreline for the straight in [to] runway two three." The pilot responded, "ok straight in for two three thanks."
At 1457:42, the pilot of N99063 reported to UGN ATCT that she was holding short of runway 23 and was "ready for departure." The LC instructed N99063 to "hold short." The pilot acknowledged. At 1457:57, the LC instructed N99063 to "taxi into position and hold," and, 10 seconds later, he cleared N99063 for takeoff.
At 1459:48, the LC asked the pilot of N5ZA for his position. The pilot replied that he was "just about a mile or two off the lake...off the shoreline." (However radar data from Chicago TRACON showed that N5ZA was actually 3.75 miles northeast of the shore along the runway 23 extended centerline [approximately 7.75 miles from the end of the runway] and 2.7 miles from shore, with the shoreline being abeam to the right side of the aircraft.) At 1459:53, the LC asked the pilot, "are you straight in still?" The pilot responded, "ah yes sir." The LC instructed the pilot to "keep your speed up as much as feasible cleared to land." The pilot acknowledged and stated, "peddling as fast as I can."
At 1500:38, the LC instructed N99063 to "continue on the downwind advise when you see a red low wing aircraft straight in on final." The pilot of N99063 responded, "looking for the traffic." (Radar data from Chicago TRACON revealed that N99063 was established on the downwind leg, approximately 0.7 mile due north of the approach end of runway 23. The radar also revealed that N5ZA was 2.3 miles northeast of the shoreline, 6.3 miles from the approach end of runway 23.) At 1500:50, the pilot of N5ZA stated, "zulu alpha's the white zlin." The LC acknowledged and transmitted to N99063, "it'll be a white low wing aircraft." The pilot of N99063 acknowledged. At 1501:16, the pilot of N99063 stated, "negative traffic," and asked the LC to advise her when to turn for her base leg. The LC acknowledged. (Radar data from Chicago TRACON showed that N99063 was approximately 1.75 miles northeast of the approach end of runway 23 and that N5ZA was 1.4 miles northeast of the shoreline, 5.3 miles from the approach end of runway 23.) In a post accident interview, the LC stated that at this point he could not see N99063 and that he had lost sight of the aircraft about 1.5 miles northeast of the field. The LC also stated that he could not see N5ZA at that time. He added that weather conditions "got hazy near the water."
At 1501:41, the LC asked the pilot of N5ZA how far out he was from the shoreline; the pilot responded that he was "just crossing the shoreline." (Radar data from Chicago TRACON showed that N5ZA was 0.8 miles from the shoreline, approximately 4.8 miles from the approach end of runway 23.) At 1502:09, the LC asked the pilot of N99063 if she saw N5ZA yet. The pilot of N99063 responded, "negative." At 1502:12, the LC asked the pilot of N99063, "have you passed the shoreline?" The pilot replied, "gettin there." (Radar data from Chicago TRACON showed that N99063 was approximately 1.6 miles from the shore along the extended downwind leg for runway 23's right-hand traffic pattern.) At 1502:16, the LC instructed N99063 to "start your base leg now." At 1502:18, the pilot acknowledged. (About the same time, radar showed N5ZA crossing the shoreline, 4 miles from the approach end of the runway 23. As the pilot of N99063 turned onto base leg, then final approach, the airplane was slightly in front of N5ZA.) In a post accident interview, the LC stated that his decision to instruct N99063 to turn was based on his estimate of the elapsed time between losing sight of N99063 and N5ZA pilot's verbal report that he had crossed the shoreline.
At 1502:47, a Cessna 172, N52048 reported, "we have the cessna." The LC transmitted, "whoever advised they have the cessna in sight you were covered." N52048 stated, "we're back on the downwind and we have the landing traffic in sight." The LC asked N52048, "is it the low wing or cessna?" N52048 replied, "it's the cessna." At 1503:04, the LC responded, "follow in behind the cessna you're number three." The pilot of N52048 acknowledged. Chicago TRACON radar showed that, at 1503:05, N52048 was 2.5 miles northeast of the approach end of runway 23 on left downwind and that N5ZA was 3 miles from the approach end of runway 23 on the extended centerline. The radar also revealed that, at 1503:08, N99063 had completed her base leg and turned to final, at a point approximately 2.7 miles from the approach end of runway 23.
At 1503:19, the pilot of N5ZA reported, "negative contact with the cessna in front of us." (Chicago TRACON radar showed that N5ZA was approximately 2.6 miles from the approach end of runway 23.) The LC replied, "you should be number one Bob." At 1503:27, the pilot of N5ZA stated, "then we have the traffic in sight, thanks." (Chicago TRACON radar showed that N99063 was established on final 2.5 miles from the approach end of runway 23 and that N52048 was on left base 3.1 miles from the approach end of runway 23.) In a post accident interview, the LC stated that at this point, "something started to click [that] something was wrong" and that he used binoculars to try to get the aircraft in sight. The LC stated that he saw N5ZA at this time but that he did not see N99063.
At 1503:38, the LC instructed the pilot of N99063 to "advise when you turn final." At 1503:40, the pilot of N99063 reported that she was on final approach. The LC stated, "thank you." At 1503:53, the LC asked N5ZA, "do you see a cessna in front of you?" At 1504:00, the pilot of N5ZA responded, "[N5ZA] just had a midair." The LC responded, "we just saw that." (Chicago TRACON's last radar target from N5ZA was received at 1503:59 and showed that N5ZA was 2 miles from the approach end of runway 23.) The LC immediately instructed all other airborne aircraft to depart the pattern.
Several witnesses on the ground stated that they had seen N5ZA strike N99063 on its left side from behind near the flap. One witness stated that he heard a "pop" when he looked up and that he saw pieces of metal come off of an airplane; however, he was unable to determine from which airplane the pieces had departed. The witness stated that N99063 was below N5ZA and that it looked as if the two airplanes' wings had touched. Another witness stated that, when she first saw the two airplanes, one airplane seemed to be following the other. She stated that, after the two airplanes collided, one airplane spiraled down, and the other airplane continued for about 1 second and then nose-dived.
N5ZA Pilot The pilot of N5ZA held a private pilot certificate with a single-engine land airplane rating. According to FAA airman records, at the time he received his private pilot certificate, on July 23, 1995, the pilot had accumulated 516 total flight hours, 462 hours of which was dual flight and 54 hours of which was solo flight. At his flight physical on December 12, 1998, the pilot reported that he had accumulated 1,200 total flight hours, 150 of which were flown in the 6 months preceding the accident. A personal logbook showed that the pilot had logged in 12.6 hours in a Moravan Z242 as of January 15, 1999. A certified flight instructor reported that he had given the pilot a biennial flight review in a Cessna Model 182 on January 16, 2000. His most recent FAA third-class medical certificate was issued on December 12, 1998, with the limitation that he wears corrective lenses for distance vision and possess corrective lenses for near vision.
N5ZA Pilot-Rated Passenger The pilot-rated passenger on board N5ZA held an airline transport pilot certificate with an airplane multiengine land rating and commercial privileges for single-engine land airplanes. At his flight physical on November 24, 1999, the pilot-rated passenger reported that he had accumulated 1,500 total flight hours, 15 of which were flown in the 6 months preceding the accident. According to his pilot logbook, the pilot-rated passenger had successfully completed a biennial flight review in a Beech BE-36 on August 15, 1999. The logbook also showed that the pilot-rated passenger had previously logged 4.1 hours in N5ZA with the accident pilot. His most recent FAA second-class medical certificate was issued on November 24, 1999, with no restrictions.
N99063 Student Pilot The student pilot of N99063 was enrolled in a professional pilot course at American Flyers, West Chicago, Illinois. She began her flight training on November 19, 1999. On January 14, 2000, the student flew her first solo flight, and her student certificate was endorsed for solo flight. According to the student pilot's logbook, as of February 7, 2000, she had accumulated 35.8 total flight hours in Cessna model 172 single-engine airplanes. Her most recent FAA third-class medical certificate was issued December 18, 1999, with the limitation that she wears corrective lenses.
Local Controller The LC began working as an air traffic controller in 1972 for the U.S. Army. He started working for the FAA in 1975. In 1981, he ceased working for the FAA and has since worked for air traffic contract companies at Topeka, Kansas, and UGN ATCT. The LC began working at UGN ATCT on May 6, 1990, shortly after the tower service was established. The LC holds control tower operator certificate number 21660634, dated May 23, 1990. The LC has served as the tower manager since October 1993. The LC's training records indicate that he was recertified on all positions on July 25, 1995, and completed controller-in-charge training on January 5, 1998. His most recent second-class medical certificate was issued July 6, 1999.
N5ZA N5ZA, a Moravan Z242L, was co-owned by the pilot and a friend and was flown for pleasure. The airplane was based at UGN. The airplane underwent an annual inspection on November 3, 1999. At that time, the total airframe time was 96.4 hours, and the recording tachometer read 38.3 hours.
N99063 N99063, a Cessna 172P, was owned by AIE of New York, Inc., Ronkonkoma, New York, and operated by the West Chicago branch of American Flyers. The airplane was based at the Palwaukee Airport, Wheeling, Illinois. The airplane was used for flight training in several courses offered by the school. The airplane underwent a 100-hour inspection on January 10, 2000. At that time, the total airframe time was 12,099.6 hours, and the recording tachometer read 1,021.7 hours. The tachometer time observed by the investigator-in-charge at the accident site was 1,081.8 hours.
About 1455, the surface weather observation taken at UGN was clear skies, 10 miles visibility, temperature 33 degrees Fahrenheit (F), dew point 23 degrees F, wind 220 degrees at 17 knots, altimeter setting of 30.19 inches of Mercury.
Several witnesses near UGN, in the air and on the ground, reported hazy conditions over Lake Michigan and along its shore.
UGN lies on the north-northwest side of Waukegan, Illinois, at latitude 42 degrees, 25.33 minutes north, and longitude 87 degrees, 52.07 minutes west. Zion, Illinois, is 2 miles north-northeast of the airport. The airport has two runways: 23 and 32. Runway 23 is 6,000 feet long and 150 feet wide and has a concrete surface. Runway 32 is 3,251 feet long and 75 feet wide and has a concrete surface. The airport is located approximately 3 miles west of Lake Michigan's shore. The approach end of runway 23 is 4 miles from the shore, as measured along the extended centerline by airport personnel. The airport is surrounded by Class D airspace up to 3,200 feet mean sea level (msl). The Chicago O'Hare International Airport's Class B airspace begins 1 mile south of the airport at 3,600 feet msl.
UGN handles approximately 100,000 aircraft operations per year. Although operations are predominantly general aviation, they also range from flight training, generated both locally and from other airports, to high-performance corporate jet operations. Many aircraft use UGN ATCT as a checkpoint to avoid having to fly into Chicago O'Hare's airspace.
UGN ATCT was established in 1989 as a Level 1 tower. The FAA funded the initial construction and equipment. In 1994, under the Federal Contract Tower Program, a private contractor, Midwest Air Traffic Control Services, was awarded the bid to operate the tower and provide controller and supervisory staffing. The FAA retains ownership of the facilities and equipment and conducts controller certification.
UGN ATCT operates from 0600 to 2000 local time, year round. Four controllers and a tower manager, who works on an operational schedule similar to the controllers, staff the tower. The contractor also provides "rovers," who are controllers certified at more than one facility that can fill in as needed.
The tower cab is equipped with radio transceivers and communications equipment. Airport lighting controls and direct reading wind and altimeter instruments are located on the tower console. Controllers use strip bays and magnetic chips to remind them about aircraft positions. An Automated Surface Observation System displays weather information to the controllers. At the time of the accident, UGN ATCT was not equipped with a Flight Data Input/Output computer or a tower radar display monitor.
WRECKAGE AND IMPACT INFORMATION
The Safety Board's on scene investigation began on February 8, 2000, at 1930. The accident scene consisted of three locations in Zion, Illinois: the impact site of N99063, the impact site of N5ZA, and a one-block area northeast of the N99063 impact site, where numerous pieces from both airplanes were found.
N5ZA Most of the airplane's main wreckage, which consisted of the charred remains of the airplane's cockpit, left and right wings, aft fuselage, and empennage, rested on top of the southwest corner of the hospital's (Midwestern Regional Medical Center) roof. The airplane's forward fuselage, including the cowling, engine, propeller hub, firewall, and instrument panel, was found suspended through a 7-foot-long, 6-foot, 6-inch-wide rectangular-shaped hole in the roof that extended to the fifth floor. Several airplane components, such as the nose wheel, canopy rail, windscreen frame, and flight and engine instruments were found on the fifth floor near the hole. Asphalt and metal roofing material around the edge of the hole was bent inward, charred, and melted. A steel I-beam, located beneath the roof at the west edge of the hole was buckled outward and charred. Numerous gravel stones, which covered the roof, had been pushed forward along the south-southeast edge of the hole and were found on the fifth floor beneath the hole.
A 15-foot-long, 34-foot-wide area of the roof, which surrounded the cockpit and wings of the airplane, was charred and melted. The cockpit area showed heavy charring. The fuselage walls surrounding the cockpit and cockpit interior were consumed by fire. The cockpit frame, side-by-side pilots' seats, and flight controls showed heavy charring. A portion of the aft fuselage skin, beginning at the pilots' seats and running aft 30 inches, was consumed by fire. A 51-inch section of the aft fuselage, beginning 30 inches aft of the pilots' seats, was charred and blistered. The remaining aft fuselage was bent downward and twisted clockwise approximately 23 degrees, and its inside stringers, ribs, cables and pulleys showed heat damage. The exterior paint showed minor blistering.
The left horizontal stabilizer and elevator were found intact, and the stabilizer was bent slightly upward at its mid-span. The exterior paint showed minor blistering. The top skin surfaces of the right horizontal stabilizer and elevator showed soot and blisters. Flight control continuity to the elevators was confirmed.
The airplane's vertical stabilizer was broken forward at the base and top-center vertical seam of the fuselage. The vertical stabilizer and the rudder were bent to the right 90 degrees. The left side of the vertical stabilizer showed several bends, skin tears, and soot across the surface. The right side showed skin tears at the base, bends from the base to mid-span, and paint blisters and soot across most of the surface. The rudder was intact and showed minor skin blisters and soot. Flight control continuity to the rudder was confirmed.
The airplane's right wing showed aft crushing along the leading edge from the wing root to the wing tip rivet line. The inboard part of the wing, including the right flap, was charred and melted. The outboard part of the wing showed charring and soot damage on the upper surface and was bent upward and over on itself, so that the top surface of the outboard section rested just above the top surface of the inboard section. A 28-inch-long, 45-degree tear in the bottom wing skin was observed beginning just outboard of the flap and running forward and outward toward the leading edge.
Heavy dark blue scratches were observed on the right wing's leading edge, approximately 8 inches inboard of the wing tear. Heavy light blue scratches were observed running longitudinally along a broken rivet seam, inboard of where the wing folded over. The right aileron was also bent upward and over with the outboard wing section. The outboard 18 inches of the aileron was charred and melted. Flight control continuity to the right aileron was confirmed. The right wing tip was consumed by fire. The right main landing gear and wheel pant were broken aft and rested aft of the flap area, next to the right side of the fuselage. The wheel pant was charred and blistered.
The airplane's left wing was crushed aft along the leading edge from the wing root to the wing tip rivet line. Most of the left wing was heavily charred and melted. The inboard 72 inches of the wing's trailing edge, including the left flap and inboard aileron, were consumed by fire. The remainder of the aileron was charred and showed heavy paint blisters. Flight control continuity to the left aileron was confirmed. The left wing tip was consumed by fire. Charred residual fabric material from the wing tip remained suspended along the longitudinally running rivet line. The left main landing gear was broken aft and consumed by fire.
Several large pieces of clear Plexiglas, approximately 12 inches square, were found embedded in patches of snow on the roof of the hospital approximately 40 feet north of the airplane's empennage. Several smaller pieces of clear Plexiglas were found on the rooftop, closer to the empennage and along the south and southeast edge of the hole.
The instrument panel was broken in several places and was charred and melted. Most of the airplane's instrumentation was broken out. The firewall and engine mounts were twisted and broken and were heavily charred and melted. The airplane's engine remained attached to the engine mounts and engine control cables, was suspended just above the floor, and was heavily charred. The propeller hub was observed intact and attached to the flange. All three propeller blades were broken out at the ring mounts. Portions of the airplane's cowling were suspended with the engine, broken open, charred, and melted. Pieces of canopy frame and windscreen frame were found on the floor beneath and right of the airplane's engine; they were bent, twisted, and charred. The airplane's nose wheel was also found resting on the floor with several flight and engine instruments and avionics components. All of these parts were charred and melted.
Pieces of wood, fiberglass, and metal leading edge strips from the airplane's three propeller blades were found within a one-block area of the accident site. The propeller blades were splintered into numerous pieces. The largest pieces were 12-inch-long sections of the propeller blade tips. Metal leading edge strips showed several white-colored scratches running chordwise across the surface. The wood propeller blade tips showed white-colored rubs in the red tip stripes and the clear-lacquered wood, just inboard of the tip stripes.
Post accident examination of the airplane's engine, engine controls, and airplane systems revealed no anomalies.
N99063 Most of the airplane was found near a 25-foot-long, 10-foot-wide spray of dirt, snow, and debris that fanned outward from a 4-foot-wide, 6-foot-long ground scar running northeastward along a 36-degree magnetic heading. The ground scar was 7 inches at its deepest point near the beginning edge. A 60-inch-long section of the airplane's outboard right wing was found 10 feet north of the ground scar. This section was broken longitudinally and crushed inward. The top wing skin showed two longitudinally running "C"-shaped dents. The first dent was inboard of the fracture and was 7 inches wide. The other dent ran inboard of the wing tip cap and was 4 inches wide. The wing tip cap was bent inward along the top. The wing tip was broken out along the longitudinal rivet line.
Fuel spray, oil drops, and numerous small pieces of metal, Plexiglas, and paper were found throughout the spray field. The airplane's nose wheel was found at the end of the ground scar; it was broken aft. The airplane's left main landing gear was found about 10 feet from the northeast edge of the ground scar; it was broken aft. The airplane's propeller was located about 14 feet from the northeast edge of the ground scar. The propeller was broken out at the flange mounting bolts and showed heavy torsional bending, chordwise scratches, and tip curling. An 8-inch-piece of one propeller blade was broken chordwise.
The airplane's main wreckage, which consisted of the airplane's engine, cabin area, left wing, inboard section of the right wing, fuselage, right main landing gear, and empennage, was located 40 feet from the northeast edge of the ground scar. The fuselage was upright and oriented on a 32-degree magnetic heading. The airplane's cowling was broken aft and found just east of the fuselage. The airplane's engine, engine mounts, and firewall were bent downward. The top, left side of the engine block was broken inward at three places. The instrument panel and glareshield were crushed aft and broken. Most of the flight and engine instruments and airplane avionics were broken out. The left control yoke was broken forward. The rudder pedals were crushed upward. The front windscreen was broken out and fragmented.
The forward cabin was broken open. The front cabin floor was crushed upward, bent downward, and twisted 28 degrees to the right. The left forward cabin wall and front door post were bent outward and buckled. The left cabin door was broken out and crushed inward. The pilot's window was broken out and fragmented. The right-side cabin wall and right door were broken out, crushed inward, and twisted aft. The right main landing gear strut was bent forward and up. The cabin ceiling was crushed inward just behind the pilots' seats. The left and right aft cabin windows and the left and right cabin rear windows were broken out.
The airplane's left wing was crushed aft along the leading edge from the wing root to the wing tip. The aft spar and top wing skin just forward of the left flap was crushed forward beginning at the wing root and running 28 inches outboard. Most of the airplane's left flap was torn out and showed jagged tears in several places. The outboard 26 inches of the flap and inboard 4 inches of the left aileron were severed laterally 7 inches aft of the flap leading edge and 2 inches aft of the left aileron's leading edge. Several of the severed, peeled-back metal tears in the flap showed red scratches and rubs in the paint running 45 degrees to the longitudinal axis of the airplane. The outer portion of the left wing and aileron were bent upward approximately 30 degrees, 58 inches inboard of the wing tip rivet line. Flight control continuity to the left aileron was confirmed. The left wing tip was broken aft longitudinally along the rivet line. The outboard 57 inches of the left wing was crushed aft and broken open 17 inches inboard of the wing tip rivet line. Pieces of wood were found embedded in several skin tears in the left wing's leading edge. The airplane's left strut was broken out at the wing and fuselage mounting bolts.
The airplane's right wing, found next to the right side of the airplane's cabin area, was broken aft and downward at the wing root. The inboard 52 inches of the leading edge was torn out aft to the front spar. The right flap was bent downward and crushed inward along the trailing edge. The right wing strut was broken 45 inches outward from the wing mounting bolt. The wing's leading edge, outboard of the strut, was crushed aft and bent downward. The right wing was broken aft longitudinally and downward approximately 53 inches outboard of the wing strut. The right aileron was broken longitudinally, approximately 55 inches outboard of its inboard edge. Flight control continuity to the right aileron was confirmed.
The left aft cabin wall and baggage compartment door area was crushed inward and bent aft. The left side of the aft fuselage, from the baggage door aft to the leading edge of the horizontal stabilizer, was crushed inward. The bottom of the aft fuselage was bent inward.
The empennage was intact and found bent 40 degrees right, just forward of the horizontal stabilizer's leading edge. The fin was crushed inward, bent right, and broken at the vertical stabilizer. The vertical stabilizer was crushed inward and bent to the left approximately 10 degrees. The left side of the vertical stabilizer showed several green-colored, vertically running scratches, beginning at the root of the left horizontal stabilizer and tailcone rivet line and running vertically up the side approximately 16 inches. Several white-colored scuffs and light blue longitudinally running stripes were observed on the upper left tailcone faring at the base of the vertical stabilizer. The rudder's trailing edge was crushed forward beginning at the butt of the rudder and proceeding upward to just beneath where the top rudder hinge was located. The top of the rudder, containing the counterweight and the top hinge, was broken aft. The bottom 26 inches of the rudder showed a "C"-shaped inward crush area, beginning at the trailing edge and pressing inward to the hinge line, forming a flattened area approximately 7 inches wide and 21 inches long. Several white and green paint scrapes ran vertically up the flattened out area of the rudder. Flight control continuity to the rudder was confirmed.
The left horizontal stabilizer was crushed inward and down along the leading edge beginning just outboard of the root and running outward to the tip. The outboard edge of the left elevator was bent upward and crushed inward. Several longitudinally running green- and white-colored scratches were observed in the top skin surface of the left elevator and horizontal stabilizer.
The right horizontal stabilizer showed minor dents and wrinkles. The right leading edge cap was broken. The top skin showed several black scuff marks, approximately 20 inches long, running laterally along the stabilizer at mid-span. The right elevator showed several tears in the upper skin forward of the trim tab. The trailing outboard edge of the elevator, outboard of the trim tab, was bent inward. The outboard 7 inches of the elevator trim tab was torn and bent inward. Flight control continuity to the elevator was confirmed.
A large section of the airplane's left flap, numerous small metal pieces, and three pieces of clear Plexiglas were found within the same one block area where the N5ZA propeller pieces were found. Several of the metal pieces showed red-colored scratches running parallel across the surfaces.
Post accident examinations of the airplane's engine, engine controls, and other airplane systems revealed no anomalies. N99063's left inboard flap section, wood samples from N5ZA's propeller hub, and several wood shard pieces found in the third debris field were retained for further testing.
At 1506, the Zion Emergency 911 Communications Center received a call regarding the collision. The Zion Fire Department requested multiple level alarms for additional fire department units to assist in putting the fire out and to provide ambulances to transport patients from the hospital impacted by N5ZA to other medical facilities (about 40 patients and hospital staff were evacuated from the hospital). Twenty-five fire departments from the surrounding area responded to the accident site.
The hospital received severe fire damage near and around the hole made at impact. A subsequent fire and explosion caused severe damage to fifth floor offices and a conference room.
MEDICAL AND PATHOLOGICAL INFORMATION
Autopsies of N5ZA's pilot and pilot-rated passenger and N99063's pilot were performed on February 9, 2000, at the Lake County Medical Examiner's Office, Waukegan, Illinois. The autopsies revealed no evidence of physical incapacitation or impairment. The results of FAA toxicology testing of specimens obtained from N5ZA's pilot-rated passenger and N99063's pilot were negative for all tests conducted.
FAA toxicology testing of specimens obtained from the N5ZA pilot revealed the following:
0.369 (ug/ml, ug/g) Pseudoephedrine detected in blood. 3.046 (ug/ml, ug/g) Pseudoephedrine detected in liver. 0.237 (ug/ml, ug/g) Phenylpropanolamine detected in liver.
According to the 1998 Physicians' Desk Reference, Pseudoephedrine Hydrochloride functions as an oral nasal decongestant with minimal central nervous system stimulation. It states that it is often used for "the temporary relief of symptoms of seasonal and perennial allergic rhinitis and vasomotor rhinitis, including nasal obstruction (congestion)." Warnings are directed at patients with hypertension, diabetes mellitus, ischemic heart disease, hyperthyroidism, increased intraocular pressure, and prostatic hypertrophy. The Physicians' Desk Reference further states, "antihistamines may cause excitability, especially in children. At dosages higher than the recommended dose, nervousness, dizziness or sleeplessness may occur." Pseudoephedrine Hydrochloride is contained in many over-the-counter cold and sinus medications.
The Physicians' Desk Reference states that Phenylpropanolamine shrinks swollen mucous membranes; reduces tissue hyperemia, edema, and nasal congestion; and increases nasal airways. Medications containing Phenylpropanolamine are prescribed for the relief of troublesome coughs, nasal congestion, and postnasal drip associated with colds, nasal allergies, sinusitis, and rhinitis. These medications are also used in the relief of severe, prolonged, or refractory cough associated with other respiratory disorders and for the relief of symptoms associated with "allergic rhinitis such as sneezing, rhinorrhea, pruritus, and lacrimation." Phenylpropanolamine is contained in many prescribed expectorants.
14 CFR Part 91, Paragraph 91.17, "Alcohol or Drugs," contains no specific restrictions regarding the use of either drug while operating aircraft.
TESTS AND RESEARCH
Another Moravan Z242L and Cessna 172P were examined to determine the pilots' fields of vision. The Moravan Z242L was examined to determine the pilots' fields of vision from the left and right seats. The Cessna 172P was examined to determine the pilot's field of vision from the left seat only. The measurements were taken with the airplanes parked and their engines off.
The Moravan Z242L has side-by-side seating and dual flight controls and instruments. The airplane has a "bubble" canopy, which affords unrestricted visibility for 360 degrees in a horizontal plane parallel to the longitudinal and lateral axis of the airplane and approximately 180 degrees of "overhead" visibility, when drawing a line parallel to the airplane's lateral axis, left being zero degrees, and proceeding over the top of the canopy to the other end of the line, right being 180 degrees. From the pilot's (left) seat, forward visibility is restricted by the airplane's engine cowling, providing the pilot 10-degrees-down angle visibility directly in front of the nose and 35-degrees-down angle visibility at a point off of the cowling 50 degrees left of a line running through the left seat, parallel to the longitudinal axis of the airplane. From the left seat, looking across the cockpit to the right side, the visibility is restricted by the top right corner of the instrument panel and the right canopy rail. Down angle visibility over the corner of the instrument panel is 17 degrees. Down angle visibility over the canopy rail to a point on the leading edge of the right wing, 58 inches outboard of the right wing root is 29 degrees. Down angle visibility to the leading edge corner of the right wing tip is 8 degrees from the left seat. Left side, down visibility from the left seat is partially restricted by the low left wing. Downward visibility is 50 degrees at the leading edge of the wing, 26 inches outboard of the wing root, 26 degrees at the leading edge of the wing at mid-span, and 14 degrees at the leading edge of the wing tip. Visibility measures for the Moravan Z242L's right seat occupant mirror those of the left seat occupant. All visibility measures on the Moravan Z242L were based on a person with a seating height of 36 inches.
The Cessna 172P has side-by-side seating in the front and a rear couch (two seats) in the back of the cabin. The airplane has dual flight controls and instruments. The Cessna 172P has a high wing, which also constitutes the roof of the airplane's cabin. The "bubbled" windscreen provides unrestricted forward visibility from the left pilot's seat. Downward visibility is partially restricted by the airplane's cowling. Downward visibility directly in front of the pilot is 8 degrees. Downward visibility, 45 degrees left of a line running parallel to the longitudinal axis of the airplane and through the left pilot seat, is 40 degrees. Lateral visibility from the left pilot seat, through the front windscreen, is 180 degrees. Downward visibility through the left seat window is 60 degrees. Visibility across the cabin through the right window provides a 16-degree vertical cone, with the top of the cone bordered by the right wing and the bottom of the cone bordered by the bottom of the right seat window. The cabin ceiling restricts the pilot's overhead visibility. Visibility directly behind the airplane is limited through two rear windows, one on left side of the airplane and the other on the right, and two aft cabin windows, one on the left side and the other on the right. Direct rear visibility through the aft windows is restricted to a 6-degree cone, which is achieved only when the pilot turns her head inboard and looks aft. Top, rear visibility is obstructed by the left and right wings and the aft cabin ceiling. A 126-degree-wide semicircle, beginning at a point off the pilot's left shoulder and running counter-clockwise along the trailing edge of the left wing, the tops of the aft window frames, along the trailing edge of the right wing, to a point off the pilot's right shoulder and forward to a point 36 degrees forward of a vertical axis running through the left pilot's seat, is blocked from the pilot's field of vision. All visibility measures on the Cessna 172P were based on a person with a seating height of 32 inches.
The wood splinters embedded in N99063's left inboard flap section, the wood samples taken from N5ZA's propeller hub, and the wood shards found in the third debris field were examined by the United States Department of Agriculture, Forest Products Laboratory, Madison, Wisconsin, on April 20, 2000, and determined to be Sitka spruce (Picea sitchensis). Department of Transportation, FAA Publication EA-AC 65-15A, "Airframe and Powerplant Mechanics, Airframe Handbook," figure 5-108, cites spruce as the standard for comparison of other woods when determining wood materials in aircraft construction.
Parties to the investigation were the FAA's Flight Standards District Office, West Chicago, Illinois; the Cessna Aircraft Company, Wichita, Kansas; and Textron Lycoming, Williamsport, Pennsylvania.
The remains of both airplanes were released to United States Aviation Underwriters, Chicago, Illinois. On March 24, 2000, the FAA announced that a Terminal Automated Radar Display and Information System would be installed at the UGN ATCT.