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On March 30, 2011, at 1746 eastern daylight time, a Beech 58, N569JL, operated by Jet Logistics, Inc., was substantially damaged when it impacted trees and a residence while conducting an instrument approach to Piedmont-Triad International Airport (GSO), Greensboro, North Carolina. The certificated airline transport pilot and passenger were fatally injured. Instrument meteorological conditions (IMC) prevailed, and an instrument flight rules (IFR) flight plan was filed for the flight, which departed Wilmington International Airport (ILM), Wilmington, North Carolina, and was destined for Smith Reynolds Airport (INT), Winston Salem, North Carolina. The non-scheduled passenger flight was conducted under the provisions of Title 14 Code of Federal Regulations (CFR) Part 135.
Personnel records provided by the operator indicated that, on the day preceding the accident, the pilot reported for duty at 1030 after having been off duty for several days. The pilot acted as second-in-command of a Beech 90 during a two-leg trip, and reported off duty at 1830. Review of data provided by a third-party flight planning and weather briefing service showed that, at 2053, the pilot obtained a weather briefing encompassing the series of airports she was scheduled to fly to the following day.
On the day of the accident flight, the pilot was scheduled to fly a multi-leg trip originating from the operator's base at Raleigh-Durham International Airport (RDU), Raleigh/Durham, North Carolina. The pilot was then scheduled to reposition the airplane in order to pick up a passenger at INT, and then proceed to ILM. The pilot would then reverse the circuit, eventually returning to RDU at the conclusion of the day.
That morning, the pilot queried the weather and flight planning service several times between 0437 and 0443. According to a receipt recovered from the wreckage, the pilot obtained catering refreshments at 0534. At 0644, the pilot advised the operator via electronic messaging that she was departing from RDU, en route to INT.
The airplane arrived at INT at 0739, and the pilot obtained a weather briefing for the next scheduled leg of the flight, and at 0840, advised the operator she was departing INT for ILM.
The flight subsequently arrived at ILM about 1000. Between 1454 and 1551, the pilot submitted numerous weather queries for the return portion of the flight via an internet flight planning service, including requesting weather from numerous other airports in the vicinity of the destination. At 1552, the pilot contacted a fellow company pilot asking for assistance with finding a legal alternate airport for the upcoming flight from ILM to INT. The pilots discussed possible alternatives, including GSO. At 1611, the pilot advised the operator that she was departing ILM en route to INT.
According to air traffic control (ATC) radar and voice data provided by the Federal Aviation Administration (FAA), the pilot requested and was given an IFR clearance about 1600. The flight departed ILM about 1622, and during the departure, the pilot advised the air traffic controller that the base of the overcast ceiling was 600 feet. The pilot was then cleared on course, and after speaking with several different ATC facilities en route to INT, contacted GSO approach at 1704. Upon receiving updated weather conditions at INT from the controller, the pilot advised that she would need to be placed into a holding pattern, due to the ceilings at INT being below 200 feet. At 1708, the pilot was cleared to hold at the INGON intersection, which was the published missed approach holding point for the instrument landing system (ILS) approach to runway 33 at INT.
At 1711, the GSO approach controller advised the pilot that the weather conditions at Statesville, Burlington, and Mount Airy, North Carolina, located between 25 and 40 nautical miles from INT, included cloud ceilings of at least 300 feet. The pilot advised the controller, "…that's hopeful but yeah we want to go to Wilmington…" Shortly thereafter, the GSO approach controller contacted the INT tower controller and advised that the pilot would be entering a holding pattern at INGON, and requested to be notified when the weather at INT had improved. The pilot reported entering the holding pattern at INGON at 1725. About 5 minutes later, a new approach controller came on duty and was briefed by the outgoing controller. During the briefing, the outgoing controller stated that most of the arrivals were being conducted to runway 5L as the runway visual range (RVR) on runway 5R was lower. He further stated that the most recent cloud base report was from an airplane that had departed about 30 minutes prior, and had reported that the clouds were at 50 feet. Additionally, two other aircraft had arrived at the airport and, "nobody's going around yet." The outgoing controller then also provided a briefing on each of the flights in the area, and stated that the accident airplane was holding at INGON with the pilot waiting for the ceilings at INT to improve, and that he expected the INT tower controller to advise when that happened.
At 1734, the pilot contacted the GSO approach controller and stated that after discussing the issue with her passenger, proceeding to GSO would be an acceptable alternative if the weather conditions were "good." The controller immediately cleared the pilot to GSO via radar vectors. At 1735, the controller advised the pilot that the ceiling at GSO was overcast at 100 feet, to which the pilot responded, "That's not going to help much..." Two minutes later, at 1737, the controller asked the pilot her intentions. The pilot responded that if no other aircraft were arriving at GSO, she would return to the previous holding pattern. The controller responded, "Everybody's getting into Greensboro, nobody's gone around yet," to which the pilot replied, "Alright, let's do it." The controller then began vectoring the pilot for the ILS approach to runway 5L at GSO [see the AIRPORT INFORMATION section of this report for a detailed description of the ILS RWY 5L instrument approach procedure].
At 1740, the pilot was cleared to descend to 3,000 feet and was given a radar vector to intercept the localizer for runway 5L. After passing through the localizer course from the northwest about 1 minute later, the pilot turned the airplane and re-intercepted the localizer course from the southeast. The controller contacted the pilot to advise and provide assistance if necessary, and the pilot declined.
After establishing the airplane on the localizer and being cleared for the approach, the pilot descended the airplane to the published minimum altitude of 2,500 feet for the intermediate segment of the approach. The controller advised the pilot to contact the GSO tower controller, at 1743. Upon contacting the tower controller, the pilot was advised that the RVR for runway 5L was 4,000 feet and that she was number two to land behind an Embraer 145 that was 1 mile from the runway threshold.
At 1744:33, about 0.5 nautical miles from the final approach fix, the airplane began descending from 2,500 feet, and crossed the fix about 200 feet below the published intercept altitude. Over the next 2 nautical miles, and over the course of about 2 minutes, the airplane descended to 1,300 feet, and remained below the calculated glideslope for the final 8 nautical miles of the approach. Upon reaching 1,300 feet msl, the airplane was about 400 feet above ground level and about 3 nautical miles from the runway 5L threshold. The airplane then began climbing at 1745:42, and about that time, the GSO tower controller issued a low altitude alert to the pilot. The pilot responded, "we're goin' around." The controller subsequently advised the pilot to fly the runway heading, and to climb to 4,000 feet, and the pilot acknowledged the instructions. No further transmissions were received from the pilot. After reaching 1,600 feet at 1745:52, the airplane descended to 1,500 feet at 1745:56, about the time the pilot concluded her final radio transmission. No further radar targets were observed.
The pilot held an airline transport pilot certificate with a rating for multi-engine land, and a private pilot certificate with a rating for airplane single engine land. According to the pilot's FAA Airman File, she obtained her private pilot certificate in 1984, her instrument rating in 2000, and her commercial pilot certificate in 2001. The pilot was issued second-in-command (SIC) type ratings in the LR-45 and BE-400 in 2007, and a pilot-in-command (PIC) type rating in the BE-400/MU-300 when she was issued her airline transport pilot certificate in 2008. The pilot was issued a LR-JET SIC type rating in October 2010.
Review of company records revealed that the pilot was hired by the operator in March 2010, and at that time had reported 2,590 total hours of flight experience, 770 hours of which were acting as PIC. The operator provided training to the pilot in the accident airplane, and she was found proficient to act as PIC on March 30, 2010.
The operator provided the pilot with 6 hours of flight training in preparation for her LR-JET SIC type rating. During three simulator sessions while acting as second-in-command, the pilot satisfactorily completed precision, non-precision, circling, and missed approach procedures. During this training session, the operator also certified that the pilot completed the required 6-month instrument proficiency check in accordance with CFR 135.297, on October 26, 2010.
According to company records, as of the date of the accident flight the pilot had accumulated 2,884 total hours of flight experience, 856 hours of which were acting as a PIC. The pilot also logged 117 total hours of flight experience in the accident airplane make and model, 95 hours of which were acting as a PIC. Between the time of the pilot's most recent instrument proficiency check in October and the day prior to the accident flight, she had logged 4 instrument approaches (1 approach in a LR-55, and 3 approaches in the accident airplane), and 5 hours of instrument flight experience in the accident airplane. Review of FAA ATC voice communications showed that the pilot also completed two ILS approaches during her earlier flights to INT and ILM on the day of the accident.
The airplane was manufactured in 1975, and was equipped with two 285-horsepower Teledyne Continental Motors IO-520 reciprocating engines. According to company records, the airplane's most recent annual inspection was conducted on November 8, 2010.
The airplane was equipped with a Garmin GNS 530W multi-function navigation and communication system. According to the Garmin 500 W Series Pilot's Guide and Reference, the unit featured a non-certified terrain awareness system, or an optional certified Terrain Awareness and Warning System (TAWS). The accident airplane was not equipped with a certified TAWS installation, nor was it required to be. The non-certified Terrain feature displayed terrain and obstructions relative to the altitude of the airplane, and displayed alerts that were advisory in nature. The unit utilized terrain and obstacle databases to display a 2-dimensional picture of the surrounding terrain and could use position and altitude information to predict the airplane's flight path with relation to that terrain, in order to provide the pilot with an advanced alert of a predicted dangerous terrain condition. While this system was installed in the accident airplane, the use of the non-certified terrain awareness system was not authorized by the operator’s Operations Specifications.
One of the available warnings was the Premature Descent Alert (PDA), which would issue an alert to the pilot when the system detected that the airplane was significantly below the normal approach path to the runway. The advisory envelope would provide alerts from between 0.5 and 15 miles of the runway threshold, at altitudes that decreased as the airplane approached the runway. Interpretation of the PDA Threshold chart published in the guide showed that alerts would have been issued if the airplane descended to the following altitudes above the ground with respect to the airplane's distance from the runway threshold: 350 feet and 5 nautical miles; 325 feet and 4 nautical miles; 275 feet and 3 nautical miles; 225 feet 2 nautical miles, 125 feet and 1 nautical mile. A review of the airplane’s radar height profile for the final portion of the instrument approach showed that the airplane never descended below a height that would have activated a PDA.
The terrain system provided an inhibit mode, designed to deactivate the PDA and the Forward Looking Terrain Avoidance visual alerts when they were deemed unnecessary by the pilot. The guide warned that pilots should use discretion when inhibiting the terrain system and always remember to enable the system when appropriate. When inhibited, terrain was available to be viewed by accessing the appropriate navigation page on the unit, but alert messages were not generated. Units configured with standard terrain advisories would restore the previously inhibit state (on/off) at startup, while TAWS-configured units would always start with alerts uninhibited.
The airplane was also equipped with a Garmin GDL 69 remote sensor that was capable of receiving broadcast weather data from the XM Satellite Radio service. The Garmin 530W was capable of serving as the display and control unit, and could display both graphic and textual weather information on the installed Garmin 530W.
No information regarding the pilot’s use of either the non-certified terrain awareness system or the satellite-delivered weather information was available for review.
The National Weather Service (NWS) Surface Analysis Chart for 1700 depicted the accident site between two major weather systems; the first located to the southeast through south and the second developing system to the west. The first system was associated with a low pressure system off the South Carolina coast with a stationary front extending northeast and southwest from the low extending off the southeast Atlantic coast and through southern Georgia to another low pressure system and a frontal wave. The second system was located west of the accident site associated with a low pressure system over eastern Tennessee with a developing cold front extending southwestward across western North Carolina, Georgia, into Alabama, with a trough of low pressure extending northward from the low into Virginia and West Virginia. The station models depicted light to heavy rain over eastern North Carolina and Virginia, and light to moderate rain over western Virginia, North Carolina, South Carolina, and eastern Tennessee along and ahead of the developing cold front. Numerous stations across the region also reported fog or mist, with overcast or obscured skies. The station model for Greensboro indicated wind from the northeast at approximately 5 knots, drizzle, and overcast skies.
The NWS Radar Mosaic for 1745 depicted a large area of rain showers and thunderstorms over eastern North Carolina with scattered light rain showers and drizzle over the Greensboro area. Since no significant weather echoes appeared in the Greensboro area, no further weather radar information was documented.
The 1745 weather observation at GSO included winds from 050 degrees at 8 knots, tower visibility 1/4 statute-mile visibility in light drizzle and fog, an overcast ceiling at 100 feet, temperature 6 degrees C, dew point 5 degrees C, and an altimeter setting of 29.84 inches of mercury. A surface visibility of 1/2-mile and trace precipitation of less than 0.01 inches was also noted.
The 1745 weather observation at INT included winds from 050 degrees at 5 knots, visibility 1 statute mile in mist, an overcast ceiling at 100 feet, temperature and dewpoint 6 degrees C, and an altimeter setting of 29.84 inches of mercury.
The NWS GSO upper air sounding was examined for cloud and stability information. The sounding indicated saturated conditions from 409 feet to approximately 10,500 feet, where the sounding had a relative humidity greater than 90 percent. A defined frontal inversion was noted at 1,519 feet to 3,096 feet agl where temperature increased with altitude. The sounding wind profile indicated a surface wind from 060 degrees at 8 knots with a critical layer at 3,000 feet, where the wind shifted abruptly to the southwest and then veered to the west with height at the base of the frontal inversion. The sounding supported the potential for moderate or greater turbulence at approximately 3,000 feet, where there was a strong vertical wind shear. The freezing level was identified at 9,934 feet.
A review of the Terminal Aerodrome Forecasts issued throughout the day of the accident indicated that the regular scheduled TAFs issued at 0740 and 1435 were amended several times, including 1248 and 1538. While low IMC were forecast for the arrival time, each amendment attempted to adjust the ceiling and visibility accordingly and continued to expect the same flight category. Visibility minimums were never forecast below the 1/2-mile minimum required for the ILS approaches available at GSO. The TAF for GSO current at the time of the accident was an amended forecast issued at 1652, and expected low IMC to prevail during the period. The forecast expected from 1700 included wind from 040 degrees at 8 knots, visibility 1/2 statute-mile in light drizzle and fog, ceiling overcast at 100 feet, with temporary conditions between 1700 and 2100 of 2 statute miles visibility in mist, and an overcast ceiling at 400 feet. The TAF for INT generally followed the same pattern of amendments and forecast weather conditions as the GSO forecast.
The Piedmont-Triad International Airport was configured with two parallel and one crosswind runway. Runway 5L was 9,000 feet long by 150 feet wide, and was oriented on a 054-degree magnetic heading. The runway was serviced by an ILS with distance measuring equipment, and was capable of providing navigation information for Category II ILS approaches. The initial approach fix (JEVEN) for the ILS RWY 5L approach was located 9.9 nautical miles from the runway threshold, and had a minimum crossing altitude of 2,500 feet msl. The glideslope intercept altitude was also 2,500 feet msl, and was co-located with the final approach fix (CIVES) for the localizer-only approach, 4.7 nautical miles from the runway threshold. The 3.0-degree glideslope had a threshold crossing height of 55 feet, and the decision altitude for all aircraft approach categories was 1,117 feet msl, or 200 feet agl. The approach also required a reported RVR of 1,800 feet. When operating on the approach under the minimums prescribed for a Category II approach, the decision height was 113 feet and the required RVR was 1,200 feet.
The missed approach procedure was to climb straight ahead until reaching 1,400 feet, followed by a climbing left turn to 330 degrees and 3,100 feet. The procedure then directed to intercept the 360-degree radial of the Greensboro very-high-frequency omni-directional range (VOR) and proceed to the MAYOS intersection.
WRECKAGE AND IMPACT INFORMATION
The initial impact point was located about 1,780 feet from the position of the final radar target, on an approximate 030-degree magnetic bearing, and was located about 2 nautical miles southwest of the runway 5L threshold, and was displaced about 800 feet left of the runway's extended centerline.
The initial impact point was located in a wooded area and was identified by numerous freshly broken tree branches and trunks. A wreckage path approximately 600 feet in length and oriented approximately 45 degrees magnetic extended through the wooded area. The airplane impacted numerous trees, some of which were as large as 12 inches in diameter. One 6-inch diameter tree branch exhibited a 45-degree cut with gray paint transfer. Fragments of the airplane, including portions of both wings, the empennage, flight control surfaces, and landing gear, were located along the wreckage path. The fuselage came to rest inside a residence and was largely consumed by a post-impact fire. Miscellaneous debris and personal effects from within the airplane were distributed along the final one-third of the wreckage path.
Flight control continuity could not be determined due to the extent of impact and fire damage. The landing gear actuator was found in a position consistent with the landing gear being retracted, and measurement of one flap actuator revealed a position consistent with the flaps being retracted. The remaining flap actuator was not recovered. The left elevator trim actuator displayed an as-found condition consistent with a full-scale tab deflection in the nose down direction, though this indication was not considered a reliable reflection of pre-impact position. The right elevator trim actuator displayed an as-found condition consistent with a five-degree trim tab deflection in the nose up direction. The rudder trim actuator displayed an as-found condition consistent with a 0 to 5 degree tab deflection in the nose left direction. The aileron trim actuator displayed an as-found condition consistent with neutral tab deflection.
Both left and right fuel selector handles were observed in the "ON" position. The left fuel selector was separated and could not be located. The right fuel selector remained attached and was verified to be in the "ON" position through the application of air pressure. Several instruments were recovered from the cockpit. None provided legible information with the exception of the airspeed indicator, which exhibited approximately 110 knots.
Both engines were separated from their respective nacelles, and came to rest within 50 feet of the main wreckage. The left engine propeller assembly separated at the engine crankshaft, and the right propeller assembly separated at the hub. Both propeller assemblies exhibited rotational signatures including s-bending, chordwise scratching, and polishing.
Rotational and valve continuity was established on the left engine, and thumb compression to all six cylinders was confirmed. The fuel pump was intact, and rotated freely by hand. The fuel pump drive coupling was intact and undamaged. The oil pump housing exhibited signatures of rotational scoring on the inside of the housing and outer tach drive cover. Dirt and grass were noted in the number 1, 2, and 4 cylinder bore areas. Ignition and fuel injection system continuity could not be established. The engine was rotated via the accessory drive pad and rotated freely with no stiffness or binding noted. Both the upper spark plugs and fuel injector nozzles were removed and exhibited normal operating signatures.
The right engine came to rest upside down, and exhibited extensive impact damage. The forward third of the engine exhibited impact damage and cracking to both crankcase halves. The crankshaft propeller flange was bent approximately 25 degrees inboard. A large portion of the number 5 cylinder head separated free from the assembly. The fuel pump separated free from the accessory section of the engine and remained attached to its respective nacelle. The throttle body and metering unit separated from its respective mounting location and remained attached to the nacelle. The fuel pump drive shaft did not rotate freely by hand. Both the upper spark plugs and fuel injector nozzles were removed and exhibited normal operating signatures. The fuel manifold valve was disassembled and residual fuel was noted. Borescope inspection of the engine revealed a significant amount of dirt and mud in the number 2 cylinder bore area.
MEDICAL AND PATHOLOGICAL INFORMATION
FAA Medical Records
The pilot’s most recent application for an FAA first-class medical certificate was made on October 12, 2010. A First Class Medical Certificate was issued on that date by the Aviation Medical Examiner (AME) with the only limitation that the “holder shall wear corrective lenses.” On the application the pilot reported a history of headaches, hay fever and allergies and prior gynecological and urological surgical procedures several years previously. For current medications, the pilot reported Esgic Plus (a combination medication for migraine headaches that contained butalbital, a sedative), an estrogen skin patch, and vitamins. No history of depression or use of anti-depressants was reported. Per FAA documents, neither the pilot’s medical history nor the physical examination revealed findings that would disqualify the applicant for the first-class medical certificate requested.
Post-Accident Findings and Toxicology
An autopsy was performed on both occupants by the Office of the Chief Medical Examiner, Chapel Hill, North Carolina. The cause of death for both occupants was "multiple blunt injuries."
The FAA's Bioaeronautical Sciences Research Laboratory, Oklahoma City, Oklahoma, performed toxicological testing on the pilot. No ethanol was detected in liver or muscle tissue. No assay for cyanide or carbon monoxide was performed since no blood sample was available for testing.
An NTSB medical officer reviewed the pilot's medical certification history, personal medical records, along with the autopsy report and FAA toxicological test results. According to the medical officer's review, Butalbital was detected in liver and kidney tissue and was consistent with a low therapeutic dose blood level for the drug. This drug was considered a short- to intermediate-acting barbiturate that was commonly combined with other drugs such as acetaminophen (Tylenol) and caffeine to treat migraine headache. It could impair mental and/or physical ability required for performance of potentially hazardous tasks.
Promethazine (Phenergan) was detected in the kidney. Promethazine was a prescription sedating antihistamine used to treat nausea, vomiting, itching and for purposes of sedation. It may cause sedation and may impair mental and/or physical ability required for the performance of potentially hazardous tasks.
Sertraline (Zoloft) was detected in the liver. Sertraline was a prescription medication used as an antidepressant. The FAA may approve its use after thorough patient evaluation and ongoing close follow-up.
Desmethylsertraline was detected in the liver. This was the predominate metabolic break down product of sertraline (Zoloft) although substantially less active than sertraline.
No blood sample was available for toxicology testing, therefore the precise blood levels, accurate predictions about a potential level of impairment, or knowledge about timing of medication ingestion, could not be determined.
According to Spatial Disorientation in Aviation (F.H. Previc and W.R. Ercoline), the otoliths (tiny organs of the inner ear), sense the acceleration of gravity and the acceleration associated with translational motions. Because the otoliths cannot distinguish between these two types of acceleration, they can only sense a combination of these two forces, the gravitoinertial force (GIF) vector. During coordinated, unaccelerated flight, the GIF vector is directed straight down through the pilot’s seat. When an airplane accelerates rapidly, however, the GIF vector is displaced aft, causing a false sensation of pitching up. This misperception, known as the somatogravic illusion, is normally dispelled when the pilot views the external horizon and/or the flight instruments. If no external horizon is visible and the flight instruments are not continuously monitored or are not correctly interpreted, however, the somatogravic illusion can persist, leading to an inaccurate understanding of airplane orientation and direction of motion. An inaccurate understanding of orientation and direction of motion is referred to as spatial disorientation, a condition that can lead to inappropriate pilot control inputs.
Spatial disorientation illusions are described extensively in FAA pilot training literature. For example, the 2012 Aeronautical Information Manual states, “A rapid acceleration during takeoff can create the illusion of being in a nose up attitude.” Similarly, the FAA Instrument Flying Handbook states, “A rapid acceleration, such as experienced during takeoff, stimulates the otolith organs in the same way as tilting the head backwards. This action creates the somatogravic illusion of being in a nose-up attitude, especially in situations without good visual references.” The Manual and the Handbook warn that, “The disoriented pilot may push the aircraft into a nose-low or dive attitude.” Identical information is included in the FAA’s Pilot Handbook of Aeronautical Knowledge. This particular illusion is so well recognized, that information about it is included in the FAA’s private pilot, instrument rating, and airline transport pilot knowledge test guides; and the FAA practical test standards for private pilots.
The only way to combat the somatogravic illusion during a climb in IFR conditions is to maintain one’s instrument scan to carefully monitor pitch attitude and vertical speed, and make control inputs to keep pitch and vertical speed within an appropriate range. Somatogravic illusions can be quite compelling, so intensive concentration may be required. If the pilot is not proficient at instrument flying, or their instrument scan is disrupted (as a result of distraction or fixation, for example) there is an increased likelihood of spatial disorientation and nose-down control inputs. If the airplane is close to the ground when this occurs, there may be insufficient time for recovery. A study of pilot transitions from VFR to IFR flight found that pilots require 21 to 36 seconds to transition to stable IFR flight after spatial orientation is lost.
Other Arrivals to GSO
Between 1724 and 1745, six airplanes successfully conducted ILS approaches to runway 5L at GSO. These aircraft included a Cessna 560XL, a Canadair Regional Jet 700, a Cirrus SR-22, two Embraer 145's, and an Embraer 170. Additionally, a Canadair Regional Jet 100 conducted an ILS approach to runway 5R at GSO, and a Beech 400 conducted an ILS approach to runway 33 at INT. With the exception of the accident flight, no other aircraft executed a missed approach procedure during that period.
Review of radar data showed that after intercepting the localizer for the ILS approach to runway 5L, the accident airplane maintained a trailing distance of more than 5 nautical miles from the Embraer 145 conducting an instrument approach ahead for the remainder of the accident flight. For the final portion of the accident flight, as the accident airplane descended below 2,000 feet msl, it trailed behind the Embraer 145 by about 1.5 minutes.
General Operations Manual
According to the operator’s General Operations Manual, Enroute Procedures, section A. Altitude Awareness; during single pilot operations, a mental note was to be made by the pilot of, “Any significant deviation from planned airspeed or planned descent rate or a deviation of the Course Deviation indicator or glide slope greater than 1/4 scale or the RMI/ADF indicator of +/- 5 degrees.”