PIPER PA46

Full Narrative

HISTORY OF FLIGHTOn December 6, 2020, about 1420 eastern standard time, a Piper PA-46-600TP, N282ST, sustained minor damage when it was involved in an incident near Leesburg, Virginia. The pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.
The pilot reported that the wind was “straight down the runway” when he landed on runway 35 at the Leesburg Executive Airport (JYO), Leesburg, Virginia. While continuing straight during the landing roll, the airplane “went careening to the left.” He stated that the right brake locked, and the right main landing gear (MLG) tire “blew” from the skidding. The pilot applied “significant” rudder and brake inputs to correct the deviation; however, he was unsuccessful, and the airplane departed the left side of the runway, coming to rest in the grass about 12 ft from the left edge of the runway and about 2,370 ft from the approach end of the runway.
Data downloaded from the airplane’s Garmin G3000 Integrated Avionics System revealed a rightward lateral acceleration following touchdown immediately followed by a significant lateral acceleration to the left and a corresponding decrease in heading and track consistent with the airplane sliding.
PERSONNEL INFORMATIONThe pilot reported 4,003 total hours of flight experience, with 67 hours in the incident airplane make and model.
AIRCRAFT INFORMATIONThe Piper PA-46-600TP M600 is a single turbine engine, propeller-driven, low wing airplane that was certified in June 2016 (See figure 1). The incident airplane was serial number (SN) 4698111.


Figure 1. Piper PA-46-600TP M600 airplane 3-view drawing.
Nose Landing Gear Steering

The nose landing gear (NLG) is attached to the engine mount at the upper end of the trunnion assembly by two trunnion bolts. The NLG strut assembly is installed in the trunnion assembly, where it rotates for nosewheel steering. The retract actuator is attached to the NLG trunnion assembly and engine mount to allow the NLG to retract aft into the wheel well. During retraction, the NLG strut and tire rotate 90° left through a mechanism that stows the NLG tire in a horizontal position.

The NLG is steerable through a 50° arc, 20° left and 30° right of center, using the rudder pedals. Primary rudder mechanical stops are installed adjacent to the rudder sector in the empennage to limit the deflection of the rudder and thus the motion of the rudder pedals. Secondary rudder pedal mechanical stops are installed in a machined aluminum fitting aft of the steering bellcrank. The secondary stops allow for a small amount of additional rudder pedal movement, as the rudder cables stretch before the stops engage the steering bellcrank. The NLG steering horn is attached to the top of the NLG strut with three bolts.

When the landing gear are extended, the right and left forward faces of the steering arm engage the right and left pads and rollers on the steering horn to transmit the linear motion of the rudder pedals to a rotational motion of the NLG strut.

Steering Horn Assembly

During manufacture, a steering horn assembly (part number 85154-012) was installed on M600 airplanes with SN 4698001 to 4698135. The assembly was the same as used on the M500 airplane and is attached to the NLG strut with three bolts through the base. A rub block is attached to the forward leg of the top plate, a large roller is attached to the top plate’s left leg, and a small roller is attached to the top plate’s right leg. The two steering pads and two steering rollers interface with the steering arm to provide nosewheel steering when the NLG is in the down position. The left roller should be up to 0.020 inch forward of the steering pad. The manufacturer discovered alignment issues with certain steering horn assemblies installed on airplanes with SN 4698102 and above, where the location of the steering pads and rollers were not consistent due to variances in the tolerance stack up. The alignment could be adjusted by machining the faces of the steering pads to achieve the necessary dimensional relationship between the pads and rollers. Starting at SN 4698136, the nose wheel steering horn and roller assembly was changed. The overall design of the new steering horn assembly, part number 46N32A009-001, did not change; however, the tolerances on certain critical dimensions were reduced.

Maintenance History

At the time of the incident, the airplane had accrued a total of 91 flight hours. The airplane received its airworthiness certificate on December 7, 2019. On January 17, 2020, the steering horn was removed from the NLG so that the steering pads could be resurfaced in accordance with the manufacturing drawing. The steering horn was reinstalled while the airplane was still at the Piper factory service center after it had accrued 5 hours total time.

The airplane manufacturer’s Warrantable 1st 50-hour inspection was completed on May 20, 2020, at which time the NLG and MLG oleo struts were serviced. The airplane had accrued 25.0 hours total time at the time of the maintenance. The most recent maintenance on the airplane was work on the avionics performed on August 7, 2020, at an airplane total time of 52.1 hours.

Landing Procedures

According to the normal procedures section of the Pilot’s Operating Handbook (POH), pilots are cautioned to promptly center the rudder just as the nosewheel touches down in crosswind conditions to prevent swerving during landing.


Figure 2. POH Normal landing procedures.
METEOROLOGICAL INFORMATIONAt 1355, the recorded weather at JYO included wind from 300° at 11 knots gusting to 19 knots. The calculated (left) crosswind component was 7.1 kts gusting to 12.2 kts.
AIRPORT INFORMATIONThe Piper PA-46-600TP M600 is a single turbine engine, propeller-driven, low wing airplane that was certified in June 2016 (See figure 1). The incident airplane was serial number (SN) 4698111.


Figure 1. Piper PA-46-600TP M600 airplane 3-view drawing.
Nose Landing Gear Steering

The nose landing gear (NLG) is attached to the engine mount at the upper end of the trunnion assembly by two trunnion bolts. The NLG strut assembly is installed in the trunnion assembly, where it rotates for nosewheel steering. The retract actuator is attached to the NLG trunnion assembly and engine mount to allow the NLG to retract aft into the wheel well. During retraction, the NLG strut and tire rotate 90° left through a mechanism that stows the NLG tire in a horizontal position.

The NLG is steerable through a 50° arc, 20° left and 30° right of center, using the rudder pedals. Primary rudder mechanical stops are installed adjacent to the rudder sector in the empennage to limit the deflection of the rudder and thus the motion of the rudder pedals. Secondary rudder pedal mechanical stops are installed in a machined aluminum fitting aft of the steering bellcrank. The secondary stops allow for a small amount of additional rudder pedal movement, as the rudder cables stretch before the stops engage the steering bellcrank. The NLG steering horn is attached to the top of the NLG strut with three bolts.

When the landing gear are extended, the right and left forward faces of the steering arm engage the right and left pads and rollers on the steering horn to transmit the linear motion of the rudder pedals to a rotational motion of the NLG strut.

Steering Horn Assembly

During manufacture, a steering horn assembly (part number 85154-012) was installed on M600 airplanes with SN 4698001 to 4698135. The assembly was the same as used on the M500 airplane and is attached to the NLG strut with three bolts through the base. A rub block is attached to the forward leg of the top plate, a large roller is attached to the top plate’s left leg, and a small roller is attached to the top plate’s right leg. The two steering pads and two steering rollers interface with the steering arm to provide nosewheel steering when the NLG is in the down position. The left roller should be up to 0.020 inch forward of the steering pad. The manufacturer discovered alignment issues with certain steering horn assemblies installed on airplanes with SN 4698102 and above, where the location of the steering pads and rollers were not consistent due to variances in the tolerance stack up. The alignment could be adjusted by machining the faces of the steering pads to achieve the necessary dimensional relationship between the pads and rollers. Starting at SN 4698136, the nose wheel steering horn and roller assembly was changed. The overall design of the new steering horn assembly, part number 46N32A009-001, did not change; however, the tolerances on certain critical dimensions were reduced.

Maintenance History

At the time of the incident, the airplane had accrued a total of 91 flight hours. The airplane received its airworthiness certificate on December 7, 2019. On January 17, 2020, the steering horn was removed from the NLG so that the steering pads could be resurfaced in accordance with the manufacturing drawing. The steering horn was reinstalled while the airplane was still at the Piper factory service center after it had accrued 5 hours total time.

The airplane manufacturer’s Warrantable 1st 50-hour inspection was completed on May 20, 2020, at which time the NLG and MLG oleo struts were serviced. The airplane had accrued 25.0 hours total time at the time of the maintenance. The most recent maintenance on the airplane was work on the avionics performed on August 7, 2020, at an airplane total time of 52.1 hours.

Landing Procedures

According to the normal procedures section of the Pilot’s Operating Handbook (POH), pilots are cautioned to promptly center the rudder just as the nosewheel touches down in crosswind conditions to prevent swerving during landing.


Figure 2. POH Normal landing procedures.
WRECKAGE AND IMPACT INFORMATIONAirplane Examination

Examination of the airplane revealed impact damage to the left wingtip just aft of the navigation light and slight buckling of the upper wing skin just inboard of the wingtip and forward of the main wing spar.

The right MLG tire was deflated and exhibited two flat spots, one that was worn through the tire. Examination of the preload bearings and brakes revealed no anomalies. The left MLG tire exhibited two flat spots; however, the tire was not worn through. The left MLG tire pressure measured 44.0 psi. At the time of the incident, the manufacturer specified a MLG tire pressure of 99-104 psi. The left main gear hub cap's schrader valve access door was not oriented to access the schrader valve. The NLG tire remained inflated, and the fork was deformed to the left about 10º. The right side tire wall markings were significantly abraded. The NLG tire pressure measured 33.3 psi. At the time of the incident, the manufacturer specified a NLG tire pressure of 92-97 psi.

The steering horn remained attached to the top of the NLG strut and exhibited areas of chipped and cracked paint, but no mechanical damage. There was a small impact mark noted on the aft face of the left side of the steering arm that serves as the left turn mechanical stop. No anomalies to rake angle or roller gap settings were noted during the examination in reference to service letter (SL) 1286, dated August 18, 2020.

Examination of the steering horn assembly at the manufacturer revealed that the left roller hole location measured 0.001-inch aft of its maximum tolerance. The right roller hole location measured 0.001-inch closer laterally to the center of the base than its maximum tolerance. The left steering pad measured 0.030-inch closer laterally to the center of the base than its maximum tolerance and the right steering pad measured 0.020-inch closer laterally to the center of the base than its maximum tolerance. All other dimensions were within the tolerances specified on the relevant manufacturing drawing(s).

Runway and Ground Scars Examination

Examination of the incident site revealed three distinct ground scars in the grass at the edge of the runway. At the runway departure point, the NLG ground scar was 4 ft from the right MLG ground scar and 8.8 ft from the left MLG ground scar measured perpendicular to the scars. There were distinct rubber transfer marks on the paved surface of runway 35 that matched the locations of the ground scars. The rubber transfer marks were traced back to their beginning points on the runway surface. The left MLG rubber transfer mark showed four parallel lines with spaces between, consistent with the tire tread pattern and the tires rolling with brakes applied. The marks were lighter in appearance for the first 85 ft then became much darker, consistent with heavier braking action. The right MLG rubber transfer mark showed four parallel lines with spaces between for the first 7 ft, then transitioned to a darker and wider line with no tread pattern consistent with a skidding tire. The dark, wide right MLG skid mark continued until about 60 feet from the departure point, where it transitioned to a very light mark. The NLG rubber transfer mark was a wider line of varying intensity with no tread pattern, consistent with a skidding tire.

Recorded Flight Data

The Garmin G3000 Integrated Avionics System on the airplane recorded certain flight parameters. Data downloaded and plotted by the manufacturer revealed the altitude, groundspeed, heading, track, pitch, and lateral acceleration data for the incident landing, shown in Figure 3. The airplane experienced an initial slight lateral acceleration to the right after the MLG touched down, followed by a more significant left lateral acceleration when the NLG touched down about 2 seconds later. The heading began to diverge left of the track when the NLG touched down. About 5 seconds after touchdown, the heading and lateral acceleration transition to the right, even though the airplane was still tracking toward the left side of the runway.


Figure 3. Plot of data from N282ST incident landing.
ADDITIONAL INFORMATIONOther Incidents

During this investigation, the NTSB was notified of similar events involving Piper PA-46-600TP airplanes. Although these events did not meet the criteria for classification as an accident, the NTSB gathered information and performed some investigative work for comparison.

N641WA Incident

On January 19, 2021, about 1615 eastern standard time, a Piper PA-46-600TP, N641WA, sustained minor damage when it departed the runway during landing at Manchester Airport (MHT), Manchester, New Hampshire. The pilot and passenger were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

The pilot reported that the airplane underwent its 50-hour inspection in late December 2020, after which he flew to Arizona, where he completed 20 hours of flight training in the airplane. The day before the event, the pilot checked the tire pressures and found them to be low. A mechanic recalled that the NLG tire pressure was about 80 psi and he added air to the tire to bring it to 92 psi. Upon landing on runway 35 at MHT, the airplane experienced a loss of directional control and a subsequent runway excursion during which the NLG collapsed. MHT airport operations examined the runway immediately following the incident and reported a dry runway and no snow or ice contamination. The wind at the time of the incident was variable at 3 kts.

Data downloaded from the airplane’s Garmin G3000 Integrated Avionics System indicated that, following NLG touchdown, there were two distinct oscillations in lateral acceleration before the excursion to the left. The G3000 wheel speed sensors were not recording at the time of the incident.

Examination of the runway revealed three distinct rubber transfer marks that led to two ground scars and the right MLG. All three transfer marks were dark, wide lines with no visible tread pattern, consistent with the tire's track angle while skidding. The three marks arced to the left throughout their length. The NLG mark was initially to the right of the left MLG mark and crossed over the left MLG mark about halfway along the length of the marks.

The NLG tire pressure was 78 psi when measured 3 days after the incident.

The airplane was equipped with the new configuration steering horn at the time of the incident. Examination of the steering horn by the manufacturer revealed that the left roller hole location measured 0.001-inch aft of its maximum tolerance, the right roller hole location measured 0.005-inch aft of its maximum tolerance, the left steering pad measured 0.020-inch closer laterally to the center of the base than its maximum tolerance, and the right steering pad measured 0.020-inch closer laterally to the center of the base than its maximum tolerance.

N831PS Incident

On December 19, 2020, about 1436 eastern standard time, a Piper PA-46-600TP, N831PS, experienced a veer to the left during landing on runway 33 at Martin State Airport (MTN), Middle River, Maryland. The pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

The pilot reported that the visual approach was normal, and he crossed the runway threshold at 85 kts. The touchdown was normal and on the runway centerline; however, when the NLG touched down, the airplane veered “hard” to the left. The pilot was able to correct the deviation and the airplane remained on the runway surface. After shutdown and a visual inspection, he returned to his home airport, where upon landing, the NLG tire pressure was 72 psi.

Data downloaded from the airplane’s Garmin G3000 Integrated Avionics System indicated that, following NLG touchdown on the incident flight, there was a left lateral acceleration about -0.12 g followed by a right lateral acceleration about 0.20 g. The lateral acceleration oscillated slightly for the next 3 seconds before becoming stable and during this time, the heading deviated from the track. The remainder of the landing roll appeared normal.

After the incident, the airplane underwent an annual inspection, during which the NLG steering horn was replaced. Examination of the steering horn assembly from the incident airplane by the manufacturer revealed that the left steering pad measured 0.020-inch closer laterally to the center of the base than its maximum tolerance and the right steering pad measured 0.040-inch closer laterally to the center of the base than its maximum tolerance.

N115NX Incidents

This Piper PA-46-600TP, N115NX, SN 4698115, experienced three separate steering events. On December 23, 2019, about 1013 central standard time, during landing on runway 18 at Johnson County Executive Airport (OJC), Olathe, Kansas, the airplane departed the right side of the runway, crossed a grassy area, and came to rest on a taxiway. The airplane was being operated by a manufacturer engineering flight test pilot as a delivery flight from the factory. The wind at the time of the incident was from 190º at 9 kts.

Examination of the airplane revealed that all tire pressures were about 10 psi low and the NLG steering pads protruded aft of the roller tangent lines about 0.074-inch. The steering horn assembly, part number 85154-012, was replaced with a new assembly, also part number 85154-012.

On June 3, 2020, the airplane veered to the right during landing on runway 22 at Driggs-Reed Memorial Airport (DIJ), Driggs, Idaho. The airplane did not leave the paved surface and was not damaged. The airplane was being operated by the owner with a flight instructor present. The wind at the time of the incident was from 210º at 11 kts. He stated that the airplane touched down and darted to the right on the incident landing. The flight instructor stated that the initial dart was to the left before the pilot corrected to the right and that the “wandering” got worse and the pilot was applying left and ruight rudder from “stop to stop.” The pilot reported that he had previously owned a PA-46-350 airplane and had recently purchased the M600.

On June 10, 2020, about 1000 mountain standard time, the airplane again veered to the right during landing on runway 4 at Winslow-Lindberg Regional Airport (INW), Winslow, Arizona. The airplane was being operated by the owner with a flight instructor present and was not damaged. The wind at the time of the incident was from 020º at 4 kts.
 
The pilot reported that the airplane touched down left of the runway centerline and the airplane was drifting left. He applied right rudder, but the airplane was not responsive. The airplane finally responded and darted right. The flight instructor reported that, during the incident landing, he had his feet on the rudder pedals to feel the pilot’s inputs. He stated that there was a left deviation during the landing, and he felt the pilot apply right rudder before NLG touchdown. When the NLG touched down, the airplane veered sharply to the right. The instructor took the airplane controls, lifted the nose, and regained directional control; however, the right MLG departed the paved runway surface. The instructor stated that the tire pressures were in the normal range before the flight and there was no evident damage or handling issues after the incident. They returned to Phoenix, where the pilot informed the flight instructor that he wished to discontinue training. The pilot reported that he parked the airplane on July 16, 2020, and had not flown it since.

Examination of the airplane in April 2021 revealed a NLG tire pressure of 62 psi. The right MLG tire exhibited a flat spot. Data was downloaded from the airplane’s Garmin G3000 Integrated Avionics System pertaining to the DIJ and INW incidents.

Data pertaining to the landing at DIJ revealed that, immediately after NLG touchdown, there was a left lateral acceleration followed by lateral acceleration oscillations right and left for the next 5 seconds. About 5 seconds after NLG touchdown, the heading and track reached their maximum difference, with the heading about 9º right of the track. About 6 seconds after NLG touchdown, there was a noticeable increase in pitch followed by a decrease in the lateral acceleration oscillation. The remainder of the landing then appeared nominal with the heading and track aligned.

Data pertaining to the landing at INW revealed that, before NLG touchdown, there was a slight left lateral acceleration that continued as the NLG touched down. About 1 second after NLG touchdown, there was a significant veer to the right with the right lateral acceleration reaching a maximum of about 0.73 g about 3 seconds after NLG touchdown. At that time, the deviation between heading and track was at its maximum, with the heading about 20º right of the track. About 5 seconds after NLG touchdown, the pitch began to increase and the heading and track became aligned again. The remainder of the landing appeared nominal with the heading and track mostly aligned.

Examination by the manufacturer of the steering horn assembly removed from the incident airplane after the first incident revealed that the right (small) roller hole measured 0.002-inch further aft that the maximum tolerance. The left (large) roller hole measured 0.004-inch further aft than the maximum tolerance. The left steering pad measured 0.020-inch closer laterally to the center of the base than its maximum tolerance and the right steering pad measured 0.010-inch closer laterally to the center of the base than its maximum tolerance.

Examination by the manufacturer of the steering horn assembly removed from the incident airplane after the third incident revealed that one steering pad measured 0.016-inch closer laterally to the center of the base than its maximum tolerance and the other steering pad measured 0.010-inch closer laterally to the center of the base than its maximum tolerance.

Published Service Information

On July 24, 2020, the airplane manufacturer issued SL 1285, Proper Tire Pressure Maintenance. The NLG tire pressures increased from 88 psi to 92-97 psi. SL 1285A was issued on January 12, 2021, to supersede SL 1285 and added information on replacement placards and a revision to the POH. SL 1285B was issued on June 15, 2021, to supersede SL 1285A and the NLG tire pressure changed to 88-92 psi. The SL also added information about temperature effects and changed the PN for the replacement placards.

On August 18, 2020, the manufacturer issued SL 1286, Nose Landing Gear Steering Components Inspection and Adjustment. The SL highlighted existing Airplane Maintenance Manual (AMM) procedures for NLG alignment, NLG rake angle adjustment, and rudder cable tension, and updated the procedures for measuring and adjusting the clearance between the NLG steering arm and steering horn rollers. It recommended compliance within 50 hours and recurring inspection every 100 hours.

SL 1286A was issued on January 21, 2021, to supersede SL 1286 for all PA-46 airplanes and contained updated nose landing gear alignment procedures for the M600 airplanes. The recommended compliance remained the same as the original, but it recommended compliance at the next scheduled maintenance visit for M600 airplanes.

SL 1286B was issued on January 28, 2021, for all PA-46 airplanes to supersede SL 1286A and added new information on rigging of the rudder-aileron interconnect for M600 airplanes. The recommended compliance remained the same as the original, but it recommended compliance at the next scheduled maintenance visit for M600 airplanes that were compliant with SL 1286 and prior to further flight for M600 airplanes that were compliant with SL 1286A.

SL 1286C was issued on March 24, 2021, to supersede SL 1286B and contained clarification of the procedures to check and adjust the clearance between the NLG steering arm and steering horn rollers and the NLG alignment. The recommended compliance time remained the same as the original, but it recommended no further action until the next recurring action for M600 airplanes that already complied with SL 1286B, compliance before further flight for M600 airplanes that already complied with SL 1286A, and compliance at the next maintenance visit for M600 airplanes that already complied with SL 1286.

SL 1286D was issued on October 15, 2021, to supersede SL 1286C and updated the clearance between the steering arm and rollers to 0.010-inch minimum when pushing the right and left rudder pedals to the stops. The recommended compliance remained the same as the original, but it recommended no further action until the next recurring action for M600 airplanes that already complied with SL 1286B or SL 1286C, compliance before further flight for M600 airplanes that already complied with SL 1286A, and compliance at the next maintenance visit for M600 airplanes that already complied with SL 1286.

On December 17, 2020, the manufacturer issued Service Bulletin (SB) 1350, Nose Landing Gear Steering Horn and Arm Assemblies Inspection, applicable to M600 airplanes with SN 4698100 through SN 4698135. Piper considered compliance with the SB mandatory at the next maintenance visit, but not to exceed 50 hours. The SB called for inspection of the steering horn and steering arm and replacement, if necessary. The aim of the SB was to make the affected airplanes compliant with the updated alignment requirements between the steering horn pads and rollers in accordance with the updated steering horn design discussed above. SB 1350A was issued on February 10, 2021, to supersede SB 1350 for the same affected airplanes and updated the torque of the bolts that attach the steering horn to the NLG strut from 25-30 in-lb to 60-75 in-lb.
TESTS AND RESEARCHPublished Service Information

On July 24, 2020, the airplane manufacturer issued SL 1285 Proper Tire Pressure Maintenance. The NLG tire pressures increased from 88 psi to 92-97 psi. SL 1285A was issued on January 12, 2021, to supersede SL 1285 and added information on replacement placards and a revision to the Pilot’s Operating Handbook (POH). SL 1285B was issued on June 15, 2021, to supersede SL 1285A and the NLG tire pressure changed to 88-92 psi. The SL also added information about temperature effects and changed the PN for the replacement placards.

On August 18, 2020, the manufacturer issued SL 1286 Nose Landing Gear Steering Components Inspection and Adjustment. The SL highlighted existing Airplane Maintenance Manual (AMM) procedures for NLG alignment, NLG rake angle adjustment, and rudder cable tension and updated the procedures for measuring and adjusting the clearance between the NLG steering arm and steering horn rollers. It recommended compliance within 50 hours and recurring inspection every 100 hours. SL 1286A was issued on January 21, 2021, to supersede SL 1286 for all PA-46 airplanes and contained updated nose landing gear alignment procedures for the M600 airplanes. The recommended compliance remained the same as the original, but it recommended compliance at the next scheduled maintenance visit for M600 airplanes. SL 1286B was issued on January 28, 2021, for all PA-46 airplanes to supersede SL 1286A and added new information on rigging of the rudder-aileron interconnect for M600 airplanes. The recommended compliance remained the same as the original, but it recommended compliance at the next scheduled maintenance visit for M600 airplanes that were compliant with SL 1286 and prior to further flight for M600 airplanes that were compliant with SL 1286A. SL 1286C was issued on March 24, 2021, to supersede SL 1286B and contained clarification of the procedures to check and adjust the clearance between the NLG steering arm and steering horn rollers and the NLG alignment. The recommended compliance time remained the same as the original, but it recommended no further action until the next recurring action for M600 airplanes that already complied with SL 1286B, compliance before further flight for M600 airplanes that already complied with SL 1286A, and compliance at the next maintenance visit for M600 airplanes that already complied with SL 1286. SL 1286D was issued on October 15, 2021, to supersede SL 1286C and updated the clearance between the steering arm and rollers to 0.010-inch minimum when pushing the right and left rudder pedals to the stops. The recommended compliance remained the same as the original, but it recommended no further action until the next recurring action for M600 airplanes that already complied with SL 1286B or SL 1286C, compliance before further flight for M600 airplanes that already complied with SL 1286A, and compliance at the next maintenance visit for M600 airplanes that already complied with SL 1286.

On December 17, 2020, the manufacturer issued Service Bulletin (SB) 1350 Nose Landing Gear Steering Horn and Arm Assemblies Inspection, applicable to M600 airplanes with SN 4698100 through SN 4698135. Piper considered compliance with the SB mandatory at the next maintenance visit but not to exceed 50 hours. The SB called for inspection of the steering horn and steering arm and replacement, if necessary. The aim of the SB was to make the affected airplanes compliant with the updated alignment requirements between the steering horn pads and rollers in accordance with the updated steering horn design discussed above. SB 1350A was issued on February 10, 2021, to supersede SB 1350 for the same affected airplanes and updated the torque of the bolts that attach the steering horn to the NLG strut from 25-30 in-lb to 60-75 in-lb.