Crash of a Cessna 525 CJ1 in Van Nuys: 2 killed

Date & Time: Jan 12, 2007 at 1107 LT
Type of aircraft:
Operator:
Registration:
N77215
Flight Phase:
Flight Type:
Survivors:
No
Site:
Schedule:
Van Nuys - Long Beach
MSN:
525-0149
YOM:
1996
Crew on board:
2
Crew fatalities:
Pax on board:
0
Pax fatalities:
Other fatalities:
Total fatalities:
2
Captain / Total flying hours:
38000
Captain / Total hours on type:
800.00
Aircraft flight hours:
3001
Circumstances:
Line personnel reported that as the airplane was being fueled, the second pilot loaded more than one bag in the left front baggage compartment. With fueling complete, line personnel saw the second pilot pull the front left baggage door down, but not lock or latch it. Witnesses near midfield of the 8,001-foot long runway, reported that the airplane was airborne, and the front left baggage door was closed. Witnesses near the end of the runway, reported that the airplane was about 200 feet above ground level (agl) and they noted that the front left baggage door was open and standing straight up. All of the witnesses reported that the airplane turned slightly left, leveled off, and was slow. The airplane began to descend, and the wings were slightly rocking before it stalled, broke right, and collided with the terrain. Investigators found no anomalies with the airframe or engines that would have precluded normal operation. The forward baggage doors' design incorporates a key lock in the lower center of each door, and two latches in the left and right bottom section of the doors. There are two hinges in the upper left and right sections of the door. The handles latched the door to the door frame in the fuselage. The key would be in the horizontal position in an unlocked condition, and in the vertical position in a locked condition. The front left baggage door was found within the main wreckage debris field and had sustained mechanical and thermal damage. The key lock was in the horizontal position. Several instances of a baggage door opening in flight have been recorded in Cessna Citation airplanes. In some cases, the door separated, and in others it remained attached. The crews of these other airplanes returned to the airport and landed successfully.
Probable cause:
The pilot's failure to maintain an adequate airspeed during the initial climb resulting in an inadvertent stall/spin. Contributing to the accident were the second pilots inadequate preflight, failure to properly secure the front baggage door, and the front left baggage door opening in flight, which likely distracted the first pilot.
Final Report:

Crash of a Piper PA-46-350P Malibu Mirage in Concord: 4 killed

Date & Time: Dec 21, 2006 at 1101 LT
Registration:
N1AM
Flight Type:
Survivors:
No
Schedule:
San Diego – Concord
MSN:
46-22061
YOM:
1989
Crew on board:
1
Crew fatalities:
Pax on board:
3
Pax fatalities:
Other fatalities:
Total fatalities:
4
Captain / Total flying hours:
3628
Captain / Total hours on type:
25.00
Aircraft flight hours:
2470
Circumstances:
While on an instrument approach for landing, the local tower air traffic controller observed on the BRITE radar repeater scope that the airplane passed the outer marker (OM), 600 feet below the permissible crossing altitude. The controller issued a low altitude alert to the pilot and cleared him to land. The controller also reminded the pilot that the minimum descent altitude for the Localizer Directional Aid (LDA) approach was 440 feet, and provided instructions for the missed approach. At that point the pilot reported that he had the airport in sight and acknowledged the landing instructions. The controller again cleared the pilot to land on the prescribed runway for the instrument approach, and the pilot acknowledged the landing clearance. Shortly thereafter the controller instructed the pilot to execute the missed approach as the radar track showed that the airplane was off course. The pilot was instructed to initiate a climbing left turn to the VOR. The pilot said he had the airport in sight and that he saw one of the cross runways and wanted to land. The controller told the pilot that circling to that runway was not an authorized procedure for the LDA approach and again instructed the pilot to perform the missed approach. A witness stated that he was working on a storage container, about 50 feet in height, when the airplane passed overhead. He estimated the airplane to be about 50 feet higher than the storage container. The airplane made a turn westbound and the witness looked away for a second. When he looked back the airplane was in a nose and left wing down attitude and then it impacted the ground. Another witness located on the airport's north-northeast corner also observed the airplane flying toward the airport. He reported simultaneously hearing the engine power up and observed the left wing stall prior to it impacting the ground. Both witnesses reported that they did not hear anything wrong with the engine. Examination of the airframe, power plant, and propeller revealed no mechanical anomalies that would have precluded normal operation. Internal damage signatures in the engine and propeller were consistent with the production of significant power at the time of impact. A review of the weather in the area revealed that while light rain and mist were occurring near the accident site, no meteorological phenomena existed that would have adversely affected the flight. The pilot and two passengers were killed while a third passenger, a boy aged 12, was seriously injured. He died from his injuries few hours later.
Probable cause:
Failure of the pilot to follow the prescribed instrument approach procedures and to maintain an adequate airspeed while maneuvering in the airport environment that led to a stall.
Final Report:

Crash of a Cessna 421B Golden Eagle II in Big Bear Lake: 3 killed

Date & Time: Nov 14, 2006 at 1013 LT
Registration:
N642BD
Flight Phase:
Survivors:
No
Schedule:
Big Bear Lake - Las Vegas
MSN:
421B-0658
YOM:
1974
Crew on board:
1
Crew fatalities:
Pax on board:
2
Pax fatalities:
Other fatalities:
Total fatalities:
3
Captain / Total flying hours:
4700
Aircraft flight hours:
4556
Circumstances:
Witnesses said that it appeared that the left engine sustained a loss of power just after rotation and liftoff. The airplane initially had a positive rate of climb, but then immediately yawed to the left as it cleared 30-foot-high power lines that were perpendicular across the flight path. The airport is at the east end of a lake in a mountain valley; the airplane departed to the west and was flying over the lake. The airplane was about 2 miles from the runway when witnesses observed dark smoke coming from the left engine, and the smoke increased significantly as the flight continued. The airplane banked hard left with the wings perpendicular to the ground, and then nosed in vertically. The landing gear remained down throughout the accident sequence. On site examination revealed that the top spark plugs for the left engine were black and sooty. A detailed examination revealed that the left turbocharger turbine wheel shaft fractured and separated. Extreme oxidation of the fracture surfaces prevented identification of the failure mode; however, the oxidation was the result of high temperature exposure indicating that the fracture occurred while the turbocharger was at elevated temperature during operation. The multiple planes exhibited by the fracture also were not consistent with a ductile torsional failure as would be expected from a sudden stoppage of either rotor. No evidence of a mechanical malfunction was noted to the right engine. The Cessna Owners Manual for the airplane notes that the most critical time for an engine failure is a 2-3 second period late in the takeoff while the airplane is accelerating from the minimum single-engine control speed of 87 KIAS to a safe single-engine speed of 106 KIAS. Although the airplane is controllable at the minimum control speed, the airplane's performance is so far below optimum that continued flight near the ground is improbable. Once 106 KIAS is achieved, altitude can more easily be maintained while the pilot retracts the landing gear and feathers the propeller. The best single-engine rate-of-climb is 108 KIAS with flaps up below 18,000 feet msl. Section VI of the manual provides operational data for single-engine climb capability. The data was only valid for the following conditions: gear and flaps retracted, inoperative propeller feathered, wing banked 5 degrees toward the operating engine, 39.5 inches of manifold pressure if below 18,000 feet, and mixture at recommended fuel flow.
Probable cause:
Failure of the turbine wheel shaft in the left turbocharger during the takeoff initial climb for undetermined reasons, and the pilot's failure to attain and maintain safe single engine airspeed that led to a loss of control.
Final Report:

Crash of a Cessna 560 Citation Encore in Upland: 1 killed

Date & Time: Jun 24, 2006 at 2226 LT
Type of aircraft:
Registration:
N486SB
Flight Type:
Survivors:
Yes
Schedule:
San Diego - Upland
MSN:
560-0580
YOM:
2001
Crew on board:
1
Crew fatalities:
Pax on board:
2
Pax fatalities:
Other fatalities:
Total fatalities:
1
Captain / Total flying hours:
2951
Captain / Total hours on type:
268.00
Aircraft flight hours:
2513
Circumstances:
The airplane touched down at night about 1,400 feet down the 3,864-foot runway and overran the runway surface, coming to rest about 851 feet beyond the departure end. The pilot was operating the airplane using a single-pilot waiver that he obtained two months prior to the accident. The airplane was certified by the Federal Aviation Administration with a flight crew of two. The pilot was returning from a personal event with his family, and landing at his home airport when the accident occurred. Witnesses stated that the pilot’s approach into the airport was not consistent with previous approaches in which the airplane would touch down directly on the runway numbers. They also stated that they heard the thrust reversers deploy, and then return to the stowed position. The airplane flight manual states that once the thrust reversers have been deployed, a pilot should not attempt to restow the thrust reversers and take off. Two sink rate warnings were issued during the approach to landing which should have alerted the pilot of the unstabilized approach. Performance calculations showed that the airplane would have required an additional 765 to 2,217 feet of runway for a full stop landing.
Probable cause:
The pilot's unstabilized approach to the runway and failure to obtain the proper touchdown point, which resulted in a runway overrun.
Final Report:

Crash of a Cessna 208B Grand Caravan in Oak Glen: 2 killed

Date & Time: Mar 28, 2006 at 1655 LT
Type of aircraft:
Operator:
Registration:
N208WE
Flight Phase:
Flight Type:
Survivors:
No
Site:
Schedule:
Thermal - Ontario
MSN:
208B-1171
YOM:
2006
Crew on board:
2
Crew fatalities:
Pax on board:
0
Pax fatalities:
Other fatalities:
Total fatalities:
2
Captain / Total flying hours:
2300
Copilot / Total flying hours:
1792
Copilot / Total hours on type:
740
Aircraft flight hours:
52
Circumstances:
The airplane was operated by the manufacturer and was on a sales demonstration itinerary. On the accident flight the airplane was being repositioned following a demonstration and the two pilots included a commercially licensed manufacturer's sales pilot and a private licensed regional sales distributor. One of the two pilots onboard requested, and received, an abbreviated weather briefing prior to departure, the details of which included an airman's meteorological information notice (AIRMET) for occasional moderate rime ice. He then filed an instrument flight rules flight plan for a route passing over mountainous terrain, with a published Minimum En route Altitude (MEA) for the airway that was above the predicted icing level. The flight plan was not activated and the pilots told a TRACON controller who was providing VFR advisories that they intended to continue under visual flight rules through a mountain pass and open their IFR flight plan after reaching the other side of the pass where the MEA was lower. A review of the mode C reported altitudes flown by the pilots and an analysis of the cloud bases and tops revealed that the flight was likely in at least intermittent, if not mostly solid, instrument meteorological conditions as it flew through the pass. As the flight approached the other end of the pass, the controller advised the pilots that the radar showed they were heading into rising terrain. The controller asked, "Do you have the terrain in sight?" One of the pilots responded, "we're maneuvering away from the terrain right now." After that, radar contact was lost. Recorded radar data showed that the airplane made a righthand turn toward rising terrain while continuing to climb to an approximate altitude of 8,800 feet mean sea level (msl). The last minute of radar data showed the airplane at altitudes of 8,000 feet msl, 8,800 feet msl, and 8,600 feet msl. The last radar return was at an altitude of 7,300 feet msl. An aircraft performance study was accomplished using recorded radar data and aerodynamic data provided by Cessna. Based on the radar data and other relevant information, as the aircraft turned toward the rising terrain, the bank angle steadily increased, until a very abrupt change in pitch consistent with a stall occurred, and the airplane departed controlled flight and descended at a very steep nose down attitude into the mountainous terrain. The airplane wreckage was subsequently located at an elevation of 6,073 feet. Nearby ground witnesses first noticed the sound of the airplane, that then suddenly changed to a high pitched increasing rpm. Witnesses then saw the accident airplane coming out of the clouds almost straight nose down. The witnesses described the weather as cold with drizzling rain and reduced visibility due to the clouds. Examination of the wreckage revealed no evidence of mechanical malfunction or failure.
Probable cause:
The pilot's continued flight into instrument meteorological weather conditions and his subsequent failure to maintain an adequate airspeed while maneuvering, that led to a stall/spin.
Final Report:

Crash of a Cessna 560 Citation V in Carlsbad: 4 killed

Date & Time: Jan 24, 2006 at 0640 LT
Type of aircraft:
Operator:
Registration:
N86CE
Survivors:
No
Schedule:
Sun Valley - Carlsbad
MSN:
560-0265
YOM:
1994
Crew on board:
2
Crew fatalities:
Pax on board:
2
Pax fatalities:
Other fatalities:
Total fatalities:
4
Captain / Total flying hours:
17000
Copilot / Total flying hours:
7500
Aircraft flight hours:
4720
Circumstances:
Air traffic control cleared the flightcrew for the instrument landing system (ILS) approach to runway 24, which was 4,897 feet long. The flightcrew then reported that they had the runway in sight, cancelled their instrument flight rules (IFR) clearance, and executed a visual flight rules (VFR) approach in VFR conditions to the airport. The reported winds favored a landing toward the east, onto the opposite runway (runway 6). During the approach, after a query from the first officer, the captain indicated to the first officer that he was going to "...land to the east," consistent with the reported winds. However, the final approach and subsequent landing were made to runway 24, which produced a six-knot tailwind. During the approach sequence the captain maintained an airspeed that was approximately 30 knots higher than the correct airspeed for the aircraft's weight, resulting in the aircraft touching down about 1,500 feet further down the runway than normal, and much faster than normal. The captain then delayed the initiation of a go-around until the first officer asked if they were going around. Although the aircraft lifted off the runway surface prior to departing the paved overrun during the delayed go-around it impacted a localizer antenna platform, whose highest non-frangible structure was located approximately 304 feet past the end of the runway, and approximately two feet lower than the terrain at the departure end of the runway. The aircraft continued airborne as it flew over downsloping terrain for about 400 more feet before colliding with the terrain and a commercial storage building that was located at an elevation approximately 80 feet lower than the terrain at the end of the runway. The localizer antenna platform was located outside of the designated runway safety area, and met all applicable FAA siting requirements. The captain had type 2 diabetes, for which he took oral medication and monitored blood sugar levels. He did not reveal his history of diabetes to the FAA. The captain's post-accident toxicology testing was consistent with an elevated average blood sugar level over the previous several months; however, no medical records of the captain's treatment were available, and the investigation could not determine if the captain's diabetes or treatment were potentially factors in the accident. The captain of the accident flight was the sole owner of a corporation that was asked by the two owners of the accident airplane to manage the airplane for them under a Part 91 business flight operation. The two owners were not pilots and had no professional aviation experience, but they desired to be flown to major domestic airports so that they could transfer and travel internationally via commercial airlines. One of the two owners stated that the purpose of the accident flight was to fly a businessman to a meeting, and to also transport one of the owner's wives to visit family at the same destination. According to one of the owners, the businessman was interested in being a third owner in the accident airplane, so the owner permitted the businessman to fly. The owner also stated that the accident pilot told him that the passenger would pay for expenses directly related to the operation of the airplane for the flight (permitted under FAA Part 91 rules), and an "hourly fee" (prohibited under FAA Part 91 rules); however, no documentation was found to corroborate this statement for the accident flight or previous flights.
Probable cause:
The captain's delayed decision to execute a balked landing (go-around) during the landing roll. Factors contributing to the accident include the captain's improper decision to land with a tailwind, his excessive airspeed on final approach, and his failure to attain a proper touchdown point during landing.
Final Report:

Crash of a Learjet 35A in Truckee: 2 killed

Date & Time: Dec 28, 2005 at 1406 LT
Type of aircraft:
Operator:
Registration:
N781RS
Flight Type:
Survivors:
No
Schedule:
Twin Falls - Truckee - Carlsbad - Monterrey
MSN:
35-218
YOM:
1978
Crew on board:
2
Crew fatalities:
Pax on board:
0
Pax fatalities:
Other fatalities:
Total fatalities:
2
Captain / Total flying hours:
4880
Captain / Total hours on type:
2200.00
Copilot / Total flying hours:
1650
Copilot / Total hours on type:
56
Aircraft flight hours:
9244
Circumstances:
The airplane collided with the ground during a low altitude, steep banked, base-to-final left turn toward the landing runway during a circling instrument approach. The airplane impacted terrain 1/3-mile from the approach end of runway 28, and north of its extended centerline. A witness, located in the airport's administration building, made the following statement regarding his observations: "I saw the aircraft in and out of the clouds in a close base for [runway] 28. I then saw the aircraft emerge from a cloud in a base to final turn [and] it appeared to be approximately 300-400 feet above the ground. The left wing was down nearly 90 degrees. The aircraft appeared north of the [runway 28] centerline. The aircraft pitched nose down approximately 30-40 degrees and appeared to do a 1/2 cartwheel on the ground before exploding." ATC controllers had cleared the airplane to perform a GPS-A (circling) approach. The published weather minimums for category C and D airplanes at the 5,900-foot mean sea level airport was 3 miles visibility, and the minimum descent altitude was 8,200 feet mean sea level (msl). Airport weather observers noted that when the accident occurred, the visibility was between 1 1/2 and 5 miles. Scattered clouds existed at 1,200 feet above ground level (7,100 feet msl), a broken ceiling existed at 1,500 feet agl (7,400 feet msl) and an overcast condition existed at 2,400 feet agl (8,300 feet msl). During the approach, the first officer acknowledged to the controller that he had received the airport's weather. The airplane overflew the airport in a southerly direction, turned east, and entered a left downwind pattern toward runway 28. A 20- to 30-knot gusty surface wind existed from 220 degrees, and the pilot inadequately compensated for the wind during his base leg-to-final approach turning maneuver. The airplane was equipped with Digital Electronic Engine Controls (DEEC) that recorded specific data bits relating to, for example, engine speed, power lever position and time. During the last 4 seconds of recorded data (flight), both of the power levers were positioned from a mid range point to apply takeoff power, and the engines responded accordingly. No evidence was found of any preimpact mechanical malfunction. The operator's flight training program emphasized that during approaches consideration of wind drift is essential, and a circling approach should not be attempted in marginal conditions.
Probable cause:
The pilot's inadequate compensation for the gusty crosswind condition and failure to maintain an adequate airspeed while maneuvering in a steep turn close to the ground.
Final Report:

Crash of a Socata TBM-700 in Lancaster

Date & Time: Dec 27, 2005 at 1446 LT
Type of aircraft:
Operator:
Registration:
N198X
Flight Type:
Survivors:
Yes
Schedule:
Camarillo - Lancaster
MSN:
138
YOM:
1998
Crew on board:
2
Crew fatalities:
Pax on board:
0
Pax fatalities:
Other fatalities:
Total fatalities:
0
Captain / Total flying hours:
6296
Captain / Total hours on type:
2921.00
Copilot / Total flying hours:
1126
Copilot / Total hours on type:
15
Aircraft flight hours:
1603
Circumstances:
The airplane stalled on short final approach, and it impacted the ground. The purpose of the flight was for the student to receive dual flight instruction to become more acquainted with the airplane's handling characteristics. The student met with his certified flight instructor and received a briefing regarding the upcoming lesson involving, in part, takeoff and landing practice. The instructor directed his student to perform a simulated engine out approach, and engine power was reduced as the airplane glided toward the airport. The student entered a close in downwind approach and, at the direction of the instructor, then performed a left circling turn onto the base and final approach legs. The landing gear was lowered, and the student questioned the instructor regarding whether they could glide all the way to the runway. The instructor advised his student to maintain 90 knots airspeed. During the descent, as the airplane turned from the close in base leg onto the final approach leg, the instructor told his student "don't bank." The student rolled the wings level. Immediately thereafter, the left bank began a second time and the instructor again said, "Don't bank." The student replied, "I'm not." The instructor applied engine power and right rudder to reduce the left bank. The airplane stopped rolling left, and then rolled into a right bank, whereupon the right wing impacted the ground. At no time did the instructor direct his student to release the airplane's flight controls.
Probable cause:
The student's failure to maintain adequate airspeed, and the instructor's inadequate supervision and delayed remedial action, which resulted in a stall/mush.
Final Report:

Crash of a Learjet 25D in Sacramento

Date & Time: Oct 26, 2005 at 1825 LT
Type of aircraft:
Operator:
Registration:
N888DV
Flight Type:
Survivors:
Yes
Schedule:
Sacramento - Sacramento
MSN:
25-370
YOM:
1984
Crew on board:
2
Crew fatalities:
Pax on board:
0
Pax fatalities:
Other fatalities:
Total fatalities:
0
Captain / Total flying hours:
17500
Captain / Total hours on type:
1100.00
Copilot / Total flying hours:
20000
Copilot / Total hours on type:
70
Circumstances:
The crew landed with the landing gear in the retracted position. While the airplane was on the base leg of the traffic pattern, the pilot heard a helicopter pilot make a transmission over the common radio frequency. As he completed the before landing checklist the pilot searched for the helicopter that he heard over the radio. During the landing flare he realized something was amiss and looked down at the instrument panel. He noticed that the landing gear lights were illuminated red. Just prior to contacting the runway surface he reached for the landing gear handle and manipulated it in the down position. The airplane made a smooth touchdown with the landing gear in the retracted position. The pilot stated that he did not make the proper check for the gear extension due to the timing of the helicopter distraction. The pilot reported no preimpact mechanical malfunctions or failures with the airplane or engine, stating that the accident was the result of pilot error.
Probable cause:
The pilot's failure to extend the landing gear and to verify they were in the down and locked position prior to touchdown. A related factor was his diverted attention.
Final Report:

Crash of a Lockheed P-3V-1 Orion near Chico: 3 killed

Date & Time: Apr 20, 2005 at 1850 LT
Type of aircraft:
Operator:
Registration:
N926AU
Flight Phase:
Flight Type:
Survivors:
No
Site:
Schedule:
Chico - Chico
MSN:
185-5171
YOM:
1963
Crew on board:
3
Crew fatalities:
Pax on board:
0
Pax fatalities:
Other fatalities:
Total fatalities:
3
Captain / Total flying hours:
4937
Captain / Total hours on type:
2915.00
Copilot / Total flying hours:
4317
Copilot / Total hours on type:
192
Aircraft flight hours:
15614
Circumstances:
Prior to the accident flight, the air tanker airplane had flown 9 times on the day of the accident, for a total flight time of 5 hours and 46 minutes. The purpose of the flights was to provide recurrent training for pilots scheduled to conduct fire-fighting operations for the United States Department of Agriculture Forest Service (USFS) during the upcoming fire season. Pilots aboard the airplane during the earlier flights reported no mechanical problems with the airplane. As was the mission for other flights that day, the accident flight, the tenth flight, was a training flight to conduct practice drops of water over an area of rugged mountainous terrain located north of the airport. Aboard the flight were the captain, the copilot, and the company's Chief Pilot, who was providing flight instruction. The Chief Pilot had been on board all the flights that day. Radar data indicated that the flight departed the airport and proceeded about 10.5 nautical miles to the north where it began maneuvering in a manner consistent with the conduct of practice water drops. The data showed the airplane entering and then following a right-hand racetrack pattern oriented northeast-southwest, during which it appeared that practice drops were being made on the southwest leg. During the last minute of the flight, the airplane was on the northeast leg of the racetrack pattern, flying up a valley that was oriented northeast-southwest with uphill being to the northeast. The airplane's flight path was initially near the middle of the valley. During the last 36 seconds of the flight, the airplane's flight path began to deviate towards the rising terrain on the eastern side of the valley. The last two radar hits show the airplane at an altitude of less than 100 feet above ground level. The airplane had completed approximately 1.75 circuits of the racetrack when the data ended with the airplane at 2,900 feet msl, heading northeast. The initial impact point was located about 2,150 feet northwest of the last radar data point at an elevation of about 2,450 feet msl, indicating the airplane entered a left descending turn and completed about 90 degrees of turn between the last radar hit and the impact. No distress calls were received from the airplane. According to local authorities, witnesses observed a "fire ball" at the time of the accident. Examination of the wreckage site revealed that the airplane impacted on about a 304 degree magnetic heading in a 40 degree left bank with the left wingtip striking the ground first. The airplane was severely fragmented and a severe post crash fire burned most of the structure and surrounding vegetation. Remnants of the entire airplane were accounted for at the wreckage site. There was no evidence of pre-existing structural failures or impact with foreign objects in any of the wreckage. All four of the engines and propellers were found at the wreckage site. The engines did not have any indications of an uncontainment, case rupture, or pre-impact in-flight fire. All four engines had damage to the compressor and/or turbine rotors that was consistent with engine operation. The cockpit engine instrumentation gages indicate that all four engines were running at about 2,200 shaft horsepower at impact. Review of the airplane's maintenance records did not reveal any chronic issues with the airplane nor any system/component anomalies that would have contributed to the accident. The airplane was equipped with neither a cockpit voice recorder (CVR) nor a flight data recorder (FDR) and Federal Aviation Regulations did not require the airplane to be so equipped. The reason for the in-flight collision with terrain could not be determined.
Probable cause:
Terrain clearance was not maintained while maneuvering for undetermined reasons. Mountainous terrain was a factor.
Final Report: