July 2001
April 30, Paintsville, Ky. / Cessna Skylane
Subscribers Only At about 18:50 eastern time, a Cessna 182Q ran out of fuel and was damaged during a forced landing near Paintsville. The pilot and passenger were not injured. The pilot said he departed Mount Sterling, Ky., with full fuel and flew 3.0 hours to Paintsville. He did not refuel and departed Paintsville at about 14:30 with a Kentucky Forest Ranger for the purpose of “fire spotting.” The pilot said he calculated an endurance of 8 hours but had been flying “about 5 hours” at the economy power setting when the engine lost power....
April 29, Marfa, Texas / Cessna Skyhawk
Subscribers Only At 23:45 central time, a Cessna 172N lost engine power and was damaged in the ensuing forced landing near Marfa. The pilot and passenger sustained minor injuries. The flight was IFR en route from Austin to El Paso when the pilot reported he was low on fuel. He landed at Culberson County Airport to refuel but was unable, so he elected to fly to Marfa for fuel. While en route to Marfa, the engine lost power. Investigators found no usable fuel aboard....
April 28, Middletown, R.I. / Beech Bonanza
Subscribers Only At about 09:30 eastern time, a Beechcraft A-36 crashed while returning to land at Newport State Airport, killing the pilot and passenger. The flight had departed when the pilot transmitted that he was returning to secure part of the cowling. A pilot waiting to take off saw the airplane flying low and slow, about 200 feet above the ground, on a tight downwind leg for runway 4. The airplane turned onto the base leg at about 100 feet agl, flying very slowly. The airplane then accelerated and banked about 70 degrees to the left. As the airplane passed the extended centerline of the runway, it leveled off and full power was applied, but the airplane struck the ground. The airplane was heavily fir...
April 28, Rockwall, Texas / Piper Meridian
Subscribers Only At 16:45 central time, the pilot of a Piper PA46-500TP lost control while landing at Rockwall Municipal Airport. The pilot and two passengers were not injured. The pilot said the airplane veered to the right after touchdown on runway 17. Rudder control inputs were ineffective and the airplane continued off the right side of the runway. The pilot aborted the landing and added full power, at which point the airplane turned back toward the runway. It struck a light on the end of the runway and continued across a road, striking a fence and a tree. An examination of the nose landing gear assembly revealed that the support structure was separated from the hydraulic actuator....
April 28, Greenville, S.C. / Aeronca Champ
Subscribers Only At about 14:45 eastern time, an Aeronca 11AC struck trees after the engine started while being hand-propped at the Greenville Downtown Airport. The pilot suffered minor injuries. The pilot obtained a ferry permit to fly the airplane to have an annual inspection. He was unable to start the engine normally and sprayed ether into the air induction system. The throttle was open approximately ½ inch and a rope had been run through the airplane to secure it. When the engine started the rope broke. The pilot grabbed the main landing gear and was hurt attempting to stop the airplane....
April 27, Venice, Fla. / Piper Seneca
Subscribers Only At about 18:45 eastern time, a Piper PA-34-200 suffered a collapsed right main gear during the landing roll at Venice Municipal Airport. The pilot and two passengers were uninjured. The pilot said the airplane touched down at 80 knots on runway 31 just south of the intersection of runway 04/22, and the brakes were not effective when he initially applied them. He pumped the brakes and they became effective, but the airplane rolled off the end of the runway despite heavy braking. Marks on the runway indicated the airplane skidded the final 250 feet of runway. The left tire was flat-spotted and the right tire was blown....
April 26, White Post, Va. / Stinson 108
Subscribers Only At 06:00 eastern time, a Stinson 108 was damaged following a loss of control during takeoff from White Post Airport. The pilot was seriously injured. Investigators said the grass on the private strip was about nine inches tall and wet, and the aircraft was covered with frost. The pilot said he pulled the aircraft from the hangar the night before because he had a meeting to attend the next morning and knew he’d be in a hurry....
April 25, Bella Bella, British Columbia / Cessna Skylane
Subscribers Only At about 15:50 Pacific time, a Cessna TR182 went missing on an IFR flight from Prince Rupert, British Columbia, to Bellingham, Wash. The pilot reported a loss of engine power and ditched the aircraft offshore Bella Bella. The uninjured pilot was rescued from the water about four hours later....
April 25, Germantown, Tenn. / Steen Skybolt
Subscribers Only At about 16:25 central time, a Steen Skybolt I crashed near Germantown after losing power. The pilot was not injured. The flight took off about 10 minutes before the accident. Investigators found about three ounces of fuel in the tank. The said he thought he had at least 12 gallons of fuel aboard at takeoff when he actually had 4 gallons....
April 24, Farmington, Mo. / Cessna Centurion
Subscribers Only At 13:45 central time, a Cessna 210L crashed near Farmington, killing the pilot and passenger. Witnesses said they heard a “popping” noise and saw the propeller depart the airplane and strike the tail of the airplane....
April 22, Hampton, N.H. / Cessna Cardinal
Subscribers Only At about 13:10 eastern time, a Cessna 177 struck trees during a go-around from the Hampton Airfield. The pilot and passenger were not injured. The pilot was landing on runway 20, a 2,100-foot turf runway, when he elected to go-around due to “extremely turbulent” conditions. As the airplane began to climb, it encountered more turbulence, and struck trees about 50 feet beyond the departure end of the runway. Nearby winds were reported from 280 degrees at 18 knots, gusts to 25 knots....
April 22, Carmel Valley, Calif. / Cessna 310
Subscribers Only At 11:08 Pacific time, a Cessna 310F struck the mountains about three miles northwest of Carmel Valley, killing the pilot. The aircraft was in IMC on an IFR flight plan. The flight departed Monterey on an instrument clearance to VFR on top and was cleared to climb on a published departure procedure course to 6,000 feet. The pilot did not fly the published procedure, nor did the aircraft climb promptly. The controller warned the pilot he was headed toward higher terrain and told him to turn northbound if he was not VFR. The flight did not turn and struck terrain about 1,700 feet on a 2,000-foot ridgeline....
April 22, Brackettville, Texas / Piper Seneca
Subscribers Only At 23:46 central time, a Piper PA34-220T crashed while maneuvering near Brackettville, killing the pilot and one passenger and leaving two passengers seriously injured. Dark-night IMC prevailed but no flight plan was filed. One surviving passenger said the flight “encountered weather.” The pilot had called FSS for weather briefings three times before departing and again while airborne....
April 21, Seattle, Wash. / Cessna Cardinal
Subscribers Only At 12:06 Pacific time, a Cessna 177 crashed immediately after liftoff from runway 13L at King County International Airport. The pilot was not injured but his passenger received minor injuries. The pilot said the aircraft started rolling to the left after liftoff and he applied right aileron, but that resulted in the roll to the left becoming accelerated. As the aircraft approached 80 degrees of bank, the left wing struck the ground and the aircraft cartwheeled. The flight was the first following wing replacement and the aileron cables had been connected backwards. The pilot said he had performed a pre-takeoff check of the aileron movement but did not realize that they had deflected in a dire...
April 20, Winchester, Va. / Piper Warrior
Subscribers Only At about 23:23 eastern time, a Piper PA-28-161 lost engine power on approach to Winchester Regional Airport and was damaged in the ensuing forced landing. The pilot was not injured. The pilot estimated the airplane had a full-tanks endurance of 4.5 hours, but after three hours aloft the left fuel gauge read “E” and the right fuel gauge indicated ¼. He attempted to land in Martinsburg, W.Va., but could not activate the pilot-controlled lighting, so he continued to his destination. The engine failed while on a 1½-mile final for runway 14. The pilot switched tanks and the engine revved briefly, then died. The left fuel tank contained about 1½ pints of fuel. The right tank was compromised in the...
April 19, Fort Lauderdale, Fla. / Piper Lance
Subscribers Only At about 16:33 eastern time, a Piper PA-32-300 crashed shortly after takeoff from Fort Lauderdale/Hollywood International Airport. The pilot was seriously injured and four passengers were killed. The flight had been cleared to take off from runway 9L about three minutes earlier. The tower controller asked the pilot if he was experiencing difficulty and he replied “slightly” and advised he may have to circle. Witnesses said the airplane was about 800 feel agl in a steep bank when the nose pitched up and then dropped....
April 19, Chapel Hill, N.C. / Piper Warrior
Subscribers Only At about 17:30 eastern time, a Piper PA-28-161 struck trees during departure from Horace Williams Airport. The flight instructor and instrument student were not injured. The flight instructor said the engine sputtered and began to lose power at 100 to 200 feet agl. The engine then lost all power and the only option was a forced landing into trees off the departure end of runway 27....
April 18, La Grange, Ky. / Cessna 152
Subscribers Only At about 20:00 eastern time, a Cessna 152 nose-dived into the ground during low-level maneuvering near La Grange, killing the student pilot. Witnesses said the pilot called his home by cell phone while airborne, saying he’d soon be flying overhead. He circled his house at 100 to 300 feet, wagging the wings. After about five minutes, the airplane flew toward a prison complex and suddenly nose-dived into the ground. No pre-crash anomalies were found. The flight instructor said he had approved the student’s solo flight to practice coordination exercises and advised the student pilot not to do “any low flying or any other inappropriate flying.” The instructor said the student “assured me he was...
April 17, Oshkosh, Wisc. / Beech Bonanza
Subscribers Only At 08:15 central time, a Beech F35 operated by Basler Turbo Conversions crashed during an approach to runway 36 at Wittman Regional Airport. The pilot was killed. The airplane was completing a 30-minute maintenance test flight....
April 16, Bountiful, Utah / Mooney M20K
Subscribers Only At 17:45 mountain time, a Mooney M20K ran off the end of the runway while landing at Skypark Airport. The four occupants were not injured. The pilot said he experienced total electrical failure shortly after takeoff and returned to the airport for a no-flap landing on runway 16. The airplane overran the 4,700-foot runway and struck a ditch....
April 14, Kent, Ohio / Cessna Centurion
Subscribers Only At about 10:45 eastern time, a Cessna T210N went off the runway during an aborted landing at Kent State University Airport. The flight instructor and student received minor injuries. The flight instructor said he had been asked by the pilot to help him with landings. They practiced landings at Ravenna, then proceeded to Kent. The pilot said he bounced the landing. A wind gust pushed the aircraft to the left edge of the runway. The CFI added power to make a go-around, then aborted the go-around and put the airplane into the grass, where the nose wheel snapped off in the mud. The CFI said the aircraft continued to settle after adding full power for a go-around, so he made a forced landing in t...
April 14, Williams, Calif. / Schleicher ASW-20
Subscribers Only At 12:45 Pacific time, a Schleicher ASW-20 glider crashed shortly after takeoff during an aero tow at Williams Glider Port, killing the pilot. A witness said that, at liftoff, the glider began a steep climb above the altitude of the tow airplane. The tow pilot cut the line and the glider dove to the ground and crashed. The glider was fitted with quick-disconnect flight control fittings to aid in disassembling the glider for trailer transport. Postaccident examination of the flight control system disclosed that the elevator control push rod was disconnected from the elevator at a quick disconnect fitting in the vertical stabilizer....
April 13, Hagerstown, Md. / Piper Seneca
Subscribers Only At about 14:30 eastern time, a Piper PA-34-200 crashed while landing at Washington County Regional Airport. The pilot was not injured. The pilot initially had flown an ILS at Martinsburg, W.Va., but encountered turbulence and wind gusts he thought exceeded the airplane’s limits. He did not land and proceeded to Hagerstown, where he flew the ILS into runway 27. Winds at the time were 30 degrees off the runway at 18 knots. As he neared the flare the wind subsided. The pilot said the airplane was hit by turbulence when it was three to five feet above the runway. The airplane porpoised several times and the nose gear collapsed. The pilot reported 2,530 hours of flight experience, of which 7.5 ho...
April 13, Gig Harbor, Wash. / Cessna Cutlass
Subscribers Only At about 19:46 Pacific time, a Cessna 172RG was damaged while landing at Tacoma Narrows Airport. The pilot was not injured. The pilot said the airplane suffered an electrical failure after taking off from runway 17. He completed a 180-degree turn to land on the opposing runway and, just before touchdown, thought he heard the prop strike the runway. He applied power for a go-around, then aborted the go-around and put the gear down to land. When the airplane touched down, the right main landing gear collapsed....
April 12, Iowa Park, Texas / Cessna 150
Subscribers Only At 03:45 central time, a Cessna 150L lost engine power after takeoff from the Wichita Valley Airpark and was damaged in the ensuing forced landing. The CFI and student pilot were not injured. The CFI told investigators he was giving his student night flight instruction practicing takeoffs and landings. After the last landing the student pilot was performing a maximum performance takeoff and the engine lost power. The CFI landed at the end of the paved runway surface and rolled off the end of the runway. A visual check of the fuel tanks showed 1/4 gallon in the left tank, and 1/2 gallon in the right tank. The pair had been flying since midnight....
April 10, Sierra Vista, Ariz. / Cirrus SR20
Subscribers Only At about 18:50 mountain time, a Cirrus SR20 struck mountains and burned northwest of Sierra Vista, killing the pilot and two passengers. Instrument conditions prevailed but no flight plan had been filed. The wreckage was located near the crest on the side of a ridgeline at 5,200 feet msl. The wreckage distribution was localized within about a 50-foot radius the impact site on the 30-degree slope of the mountain. Weather at the time was low clouds obscuring high terrain, gusting winds and freezing precipitation. The airplane ballistic recovery parachute system had not been deployed....
April 09, Vero Beach, Fla. / Piper Meridian
Subscribers Only At about 12:08 eastern time, a Piper PA-46-500TP struck trees shortly after takeoff from Vero Beach Municipal Airport, killing the pilot and passenger. About 30 seconds after being cleared for takeoff, the pilot called and stated he needed to return to the airport and land. About five seconds later he reported that they were going down near the golf course. Witnesses said the airplane climbed to about 100-200 feet, at which point it appeared to slow down and start losing altitude. It struck trees on the edge of a golf course and burned. A witness on the golf course stated he did not see any smoke coming from the airplane as it flew over his head, and he stated the engine sounded like it was...
April 08, Chino, Calif. / Piper Comanche
Subscribers Only At about 17:30 Pacific time, a Piper PA-24-250 was damaged in a wheels-up landing on runway 26 at Chino. The pilot was not injured. The pilot told investigators he initiated a go-around on his first attempted landing because the runway wasn’t clear. He forgot that he raised his landing gear. He was wearing a new noise-attenuating headset that changed the sounds he normally heard when flying his airplane. He did not recognize the gear warning horn during the accident landing. He recalled that the gear warning horn was still sounding as he removed his headset....
April 08, Telluride, Colo. / Piper Comanche
Subscribers Only At approximately 15:30 mountain time, a Piper PA-24-250 struck the runway during initial climb from Telluride Regional Airport. The three occupants were not injured. The pilot said he retracted the landing gear at about 50 feet above the ground and a gust of wind struck the airplane and forced it down onto the runway....
April 07, Rockledge, Fla. / Arnet Pereyra Aventura II
Subscribers Only At about 08:55 eastern time, an Arnet Pereyra Aventura II en route to a manufacturer’s display at Sun-n-Fun, crashed during climbout from Rockledge Airpark. The pilot was seriously injured. A witness said the aircraft was departing and was below 100 feet when he noted that its pitch attitude increased and it entered a 60-degree left bank. The witness said the aircraft stalled, snap rolled to the left, and descended straight down. ...
April 06, Pearland, Texas / Piper Pawnee
Subscribers Only At 19:53 central time, a Piper PA-25-235 struck trees in a residential area during a forced landing following a loss of engine power at Clover Field. The pilot was not injured. The pilot told investigators he returned to Clover Field after a banner-towing flight over downtown Houston but had trouble releasing the banner in the grass between the runways. He said he dragged the banner on the ground and it eventually released, but he was then too close to the end of the runway to stop, so he performed a go-around. During the go-around the airplane ran out of fuel....
April 06, Lakeland, Fla. / Cessna 182
Subscribers Only At about 18:15 eastern time, a Cessna 182Q registered to the Civil Air Patrol was damaged in a hard landing at Lakeland-Linder Regional Airport. The pilot reported no injuries. The pilot said she made a normal landing and was holding back pressure on the yoke. During the landing rollout she felt a shudder after the nose wheel touched down on the runway. She assumed she had blown a tire. She informed the control tower that she had blown a tire and rolled to a stop on the side of the runway. After exiting the airplane she observed that the nose wheel was flat and both propeller tips were curled aft. Investigators concluded the nose wheel had struck the runway first, bending the firewall and fu...
April 04, Lexington, Va. / Piper Cherokee 180
Subscribers Only At 07:05 eastern time, a Piper PA-28-180 struck a fencepost during takeoff from a private airstrip in Lexington. The pilot and passenger were not injured. The pilot told investigators he was taking off from Runway 33, a 2,200-foot grass strip with random low spots. The takeoff was attempted after several days of rain and the ground was still soggy. After liftoff, the airplane struck a 6-inch square wooden fence post at the departure end of the runway....
April 04, Osteen, Fla. / Piper Seminole
Subscribers Only At about 11:40 eastern time, a Piper PA-44-180 operated by Comair Aviation Academy collided with a ditch while making a forced landing following loss of power in one engine. The flight instructor, student and passenger were not injured. The instructor said the airplane’s right engine had failed on a flight the day before. The maintenance department worked on the magneto system and then returned the airplane to service. During a climb the right engine backfired and lost power. The instructor took control and tried to restart the engine without success. The airplane would not maintain altitude on the left engine and the instructor landed the airplane in a field....
April 01, North Las Vegas, Nev. / Cessna 172
Subscribers Only At 14:45 Pacific time, a Cessna 172M struck a fence after aborting a landing attempt on runway 12 at the North Las Vegas Airport. The pilot was not injured. The pilot told investigators the landing was normal but the airplane veered to the right on the rollout. He added left rudder but the airplane continued off the runway. He added power in an attempt to take off and, as the airplane became airborne, it went off the left side of the runway. About 25 minutes before the accident, the wind was reported as 180 at 12 knots. One minute before the accident the wind was reported as 220 at 13, gusting to 20....
Obvious Hints
Subscribers Only I never should have learned this lesson because I never should have made the flight. Mother Nature decided to demonstrate several of her most unnerving weather phenomena. We were planning a flight from Los Alamos, N.M., to Amana, Iowa, for a weekend fly-in. We expected wind over the entire area of the flight for most of the planned weekend. Because of the length of the flight, we planned to leave Thursday so as to be rested when the festivities began. The Los Alamos airport is at an elevation of 7,150 feet and is a “one way” airport. Takeoff is to the east and landing to the west, regardless of wind. As we drove to the airport from about 30 miles west of Los Alamos, the wind was causin...
Ticking Ice Bomb
As a college physics professor who uses dry ice in class, I want to underscore the danger of putting dry ice in any container that can be sealed. Pat Veillette intimates the danger: “...perhaps you have considered placing the dry ice in a tightly sealed container...you have created a pressure vessel...those have inherent risks. The situation gets even worse if you have a fire.” This beats around the bush. It should be emphatically stated that dry ice in any sealed container will create a bomb whose time or force of detonation is not easily predictable. The container could be a hard plastic ice chest with latching lid! Nor do you need a fire to make the situation worse. A few ounces o...
Blind Mischief
Subscribers Only The following information is derived from the FAA’s Service Difficulty Reports and Aviation Maintenance Alerts. ---------- While examining the wreckage of a Eurocopter BK-117, metallurgists traced the cause of the accident to fatigue cracking in multiple components of the vertical fin structure, including the skin and spar. The cracking of the skin originated at some rivet holes and grew undetected to a length of approximately 5½ inches. Without support from the skin, the adjacent spar cracked until it essentially became severed. Eventually the vertical fin failed in flight. The fatigue crack propagation in the skin was concealed by the installation of the yaw SAS servo mount supp...
NTSB Preliminary Reports
Subscribers Only The following briefs were selected from the 141 preliminary reports filed with the NTSB in April 2001. Statements in quotes were taken directly from the NTSB documents. The information is subject to change as the investigations are completed. Click here to view "Accident Totals, April." ---------- April 01, North Las Vegas, Nev. Cessna 172 At 14:45 Pacific time, a Cessna 172M struck a fence after aborting a landing attempt on runway 12 at the North Las Vegas Airport. The pilot was not injured. The pilot told investigators the landing was normal but the airplane veered to the right on the rollout. He added left rudder but the...
Spooked on Approach
Subscribers Only The late November day was made for an instrument rating: winds 170 at 4 knots, visibility 5 miles in light rain and mist, ceiling 200 feet, temperature and dewpoint both at 40º F. The airplane, a turbocharged Mooney manufactured in the mid-1980s, was made for the flight. Models of its type and vintage usually came from the factory equipped like mini-airliners, with a full complement of instruments, radios and autoflight equipment. The pilot, low time and with an instrument rating issued 10 days previously, was not, however, made for the task. He lacked the experience to fully utilize his rating and aircraft. It had been a busy flying year for the pilot, according to pilot certificat...
Best Wishes Wish List
Subscribers Only The National Transportation Safety Board has created a wish list describing its most-wanted transportation safety improvements. When it comes to aviation issues, the board specifies three areas where the FAA should take action to make flying safer. The first, reducing runway incursions, is already on the FAA’s hit list as well. Control of airplanes on the ground is problematic for the FAA because the pilots (and drivers) who cause the problems are, for the most part, oblivious to the problems they’re creating. You can talk about signage and communications all you want, but after a look at the number of people who run red lights, we’ve concluded runway incursions are a cultural phenom...
Negative Charge
Subscribers Only It’s crucial to learn the right habits from your very first flights because they form the foundation of your skills for the rest of your flying career. When the proverbial fertilizer hits the fan, people tend to revert to their earliest patterns of responses. The problem is, sometimes that’s not the right response. During a badly bounced landing for example, the pilot has very little altitude and airspeed to use in trying to execute a go around or other recovery. In most aircraft, a go-around requires bringing the nose up to about 5 degrees above the horizon and adding full power. That’s apparently what the crew of a Twin Otter tried to do after a bounced landing. This tale isn’t...
Too Fast, Too Slow
Subscribers Only Aviation is full of mysteries. Perhaps rooted in reality, they take on an almost mythical air about them. Pilots “know” they are true, without being able to justify that position and without really knowing where that knowledge came from. The downwind turn, operating lean of peak and flying on “the step” have all been part of that aviation lore – and in fact may be so still for some pilots. The fact is that many pilots treat their airplanes like it’s a complex remote control for a big screen TV. They know only enough about its operation to meet their anticipated daily needs. Instead of studying the book on the airplane and engine, they put their effort into learning to fly instrument a...
Gotcha
Subscribers Only “Any cloud connected to a severe thunderstorm carries the threat of violence.” – AC 00-6A One of the dangerous myths of aviation is that of the “all-weather” general aviation airplane. And while it’s true that modern technology has done wonders in making flying more reliable and safer, it’s important to remember that Mother Nature always has the last word. Here’s an important case in point. This mishap involved a turbocharged Piper Saratoga that broke up in flight in the vicious winds found in and around severe thunderstorms. The pilot was attempting to find his way through a band of thunderstorms, which extended from northeast to southwest over central New Mexico. Two cells ne...
Stomach for Upset
Subscribers Only Remember that pilot personality self-survey, with the half-dozen psycho babble attitudes guaranteed to make a smoking hole? There was resigned, anti-authority, impulsive, macho and invulnerable. We think a more accurate way to assess whether a pilot falls into one of these groups is to connect him to an EEG and see which button lights up following the words, “Caution wake turbulence, departing 757.” Would your button be Resigned? Impulsive? Invulnerable? If you don’t spend your spare time tearing up gyros for fun, the prospect of an uncommanded flight upset might make your blood run cold. A better-than-average grasp of airmanship may cause you to understand that the instinct to “p...
This Ain’t Horseshoes
On a gorgeous VFR day, the occupants of two airplanes never knew how close they came to having their days ruined. I watched it happen. It was time for my biennial flight review, so my instructor and I loaded up the Citabria (sans parachutes) for some airwork in the boonies west of Orlando. Then we flew north to Leesburg, an uncontrolled airport with intersecting runways. Winds were light and there was a thin layer of cumulus that started at about 2,700 feet and went up to about 4,000. Traffic was using runway 13, and there are lakes at both ends of the runway. It’s usually a quiet little airport, although occasionally there are trainers around shooting touch-and-goes or NDB approaches...
Future Flight
Subscribers Only Tucked away in labs around the country, engineers are hard at work designing the next steps in a plan that would revolutionize transportation. The goal is one any aviation buff would admire: Substantially shift personal transportation between cities from being based on personal automobiles on highways to small aircraft. The Small Aircraft Transportation System ties together the work of other NASA and industry programs that have aimed to improve the powerplants, weather capabilities and navigation complexities of small aircraft. The visionary goal is lofty – to create a way to reduce the cost of a new jet to a point comparable to a “high-end luxury vehicle” in order to reduce average door-...