Narrative:

I own and operate a 2006 piper meridian aircraft (P46T). On the occasion at issue; I had flown an ILS approach. There was no wind; the runway was dry and the runway visibility was unrestricted. I crossed the 'numbers' at 90 KIAS with 300 ft/lbs of torque. The airplane's weight was significantly beneath its permissible useful load and well within its permitted center of gravity range. The meridian relies on its nosewheel steering system for ground travel. This system is operated by the rudder pedals and allows airplane directional control during ground operations. The steering linkage includes steering rods which transmit rudder pedal operation to the bellcrank within the nose wheel well. Given this system; and consistent with my normal practical; I had neutralized the rudder pedals (equal deflection) before touching down. With gear and full flaps extended and while flaring with torque abated; my airplane's main gear contacted the asphalt at or near the runway aiming point marking between 70 KIAS and 75 KIAS. The meridian's stall speed with gear extended and full flaps is 69 KIAS. My airplane was in the center of the runway with its nose aimed directly down the center of the runway. From my perspective and the perspective of my passenger pilot; the landing was normal in every respect. When the nosewheel contacted the runway; I had my feet on the rudder pedals. The rudder pedals (steering controls) vibrated; kicking against my feet. Despite the kicking; I continued to position the rudder pedals for neutrality. Almost immediately upon runway contact; the airplane with absolute authority turned 'hard right.' without hesitation; I depressed the left rudder pedal which had no effect whatsoever. It was apparent that the airplane; by its own will; was going to exit the runway to the right. Nosewheel steering was totally ineffective. In reaction; I applied brakes hard to both main gear; left greater than right; and placed the throttle in beta. Despite these efforts; the airplane left the runway; did a ground loop and came to a stop; 90 degrees perpendicular to the runway. There was no damage to the airplane or to airport property. No one was injured. I shut down the engine using the checklist and dictated what had occurred to my passenger who transcribed my statement at that moment when the event was most 'fresh' in my mind. There are 3 clear tire impressions on the runway tracking the meridian's course of travel. These impressions start in the center of the runway a short distance beyond the runway aiming point marking. These tracks extend in an arc to the right side of the runway. From the center of the runway to the exit point from the runway; the left tire track impression is approximately 230 ft; the middle tire impression is approximately 250 ft and the right tire track impression is approximately 190 ft. The middle tire impression (the nosewheel) is noted with particularity given the fact that the nosewheel has no brake. The impression is consistently 3 3/4 inches wide. I can only conclude that the wheel was in a fixed position turned to the right; no longer responsive to the airplane's steering system and was skidding along the pavement. Pictures and measurements of these impressions have been made. The piper dealer's mechanics have extensively examined the airplane and have reported that there is no damage (although the nose gear tire and 1 main gear tire were replaced). We have been aware that pilots of P46 airframes have complained that they continue to experience unexplained runway excursions despite piper's efforts to address this concern. From a historical perspective piper; when confronted with a significant number of P46 runway excursions; issued its piper service bulletin 1106 dated january 28; 2002 which provides for design changes to enhance the effectiveness of nosewheel steering for the P46 airframe. Piper reports a marked decrease in reported runway excursions subsequent to service bulletin 1106. According to piper; prior to the implementation of service bulletin 1106; the number of runway excursions reported per year divided by the number of aircraft in the fleet was 7.6%. After the implementation of service bulletin 1106 piper reports that the percentage was reduced to .8%. Despite this reported improvement; there are some experienced pilots who are emphatically certain that the P46 airframe continues to have a design flaw which (although perhaps improved) has not been eliminated (based on the mmopa website and conversations with pilots having similar excursions). The extent of the P46 airframe pilots' concern is evidenced by piper's customer information letter entitled; 'PA46 operational & maintenance information; nose gear steering.' would this letter have been issued but for significant continued pilot concern? In its letter; piper opines that low air pressure in the nose tire and/or a reduction of clearance between the steering arm and the rollers (components of the nosewheel steering system) can contribute to runway excursions. Among other conclusions piper opines that the air pressure for the nose tire should be 70 psi and that the referenced clearance should be between 0.010 and 0.030 inches with aircraft weight on the wheels. The mechanic examining my airplane after the excursion rpted 60 psi in the nose gear tire and a clearance of 0.060. The tire had been checked and aired to 70 psi approximately 2 weeks before the excursion. My piper dealer had completed an annual inspection of the airplane in sep/08. I am satisfied and I believe piper is satisfied that such minuscule deviations were not the cause of this excursion; however; I will continue to be extremely cautious that these standards are always met. In conclusion; I am satisfied that there was no pilot error contributing to or causing this excursion. Although I do not have as much time as many pilots; I have landed my meridian and other airplanes hundreds of times without ever having any experience that even approximates this excursion. From my perspective; the nosewheel steering on my airplane failed. That failure remains of idiopathic origin. I continue to have faith in piper. Piper has reacted in a responsible manner and I appreciate what it has done and is continuing to do. Perhaps some logical explanation will eventually surface.

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Original NASA ASRS Text

Title: PA46 pilot reports a runway excursion after a normal touchdown on a dry runway with calm wind.

Narrative: I own and operate a 2006 Piper Meridian aircraft (P46T). On the occasion at issue; I had flown an ILS approach. There was no wind; the runway was dry and the runway visibility was unrestricted. I crossed the 'numbers' at 90 KIAS with 300 ft/lbs of torque. The airplane's weight was significantly beneath its permissible useful load and well within its permitted center of gravity range. The Meridian relies on its nosewheel steering system for ground travel. This system is operated by the rudder pedals and allows airplane directional control during ground operations. The steering linkage includes steering rods which transmit rudder pedal operation to the bellcrank within the nose wheel well. Given this system; and consistent with my normal practical; I had neutralized the rudder pedals (equal deflection) before touching down. With gear and full flaps extended and while flaring with torque abated; my airplane's main gear contacted the asphalt at or near the runway aiming point marking between 70 KIAS and 75 KIAS. The Meridian's stall speed with gear extended and full flaps is 69 KIAS. My airplane was in the center of the runway with its nose aimed directly down the center of the runway. From my perspective and the perspective of my passenger pilot; the landing was normal in every respect. When the nosewheel contacted the runway; I had my feet on the rudder pedals. The rudder pedals (steering controls) vibrated; kicking against my feet. Despite the kicking; I continued to position the rudder pedals for neutrality. Almost immediately upon runway contact; the airplane with absolute authority turned 'hard right.' Without hesitation; I depressed the left rudder pedal which had no effect whatsoever. It was apparent that the airplane; by its own will; was going to exit the runway to the right. Nosewheel steering was totally ineffective. In reaction; I applied brakes hard to both main gear; left greater than right; and placed the throttle in beta. Despite these efforts; the airplane left the runway; did a ground loop and came to a stop; 90 degrees perpendicular to the runway. There was no damage to the airplane or to airport property. No one was injured. I shut down the engine using the checklist and dictated what had occurred to my passenger who transcribed my statement at that moment when the event was most 'fresh' in my mind. There are 3 clear tire impressions on the runway tracking the Meridian's course of travel. These impressions start in the center of the runway a short distance beyond the runway aiming point marking. These tracks extend in an arc to the right side of the runway. From the center of the runway to the exit point from the runway; the left tire track impression is approximately 230 ft; the middle tire impression is approximately 250 ft and the right tire track impression is approximately 190 ft. The middle tire impression (the nosewheel) is noted with particularity given the fact that the nosewheel has no brake. The impression is consistently 3 3/4 inches wide. I can only conclude that the wheel was in a fixed position turned to the right; no longer responsive to the airplane's steering system and was skidding along the pavement. Pictures and measurements of these impressions have been made. The Piper dealer's mechanics have extensively examined the airplane and have reported that there is no damage (although the nose gear tire and 1 main gear tire were replaced). We have been aware that pilots of P46 airframes have complained that they continue to experience unexplained runway excursions despite Piper's efforts to address this concern. From a historical perspective Piper; when confronted with a significant number of P46 runway excursions; issued its Piper Service Bulletin 1106 Dated January 28; 2002 which provides for design changes to enhance the effectiveness of nosewheel steering for the P46 airframe. Piper reports a marked decrease in reported runway excursions subsequent to Service Bulletin 1106. According to Piper; prior to the implementation of Service Bulletin 1106; the number of runway excursions reported per year divided by the number of aircraft in the fleet was 7.6%. After the implementation of Service Bulletin 1106 Piper reports that the percentage was reduced to .8%. Despite this reported improvement; there are some experienced pilots who are emphatically certain that the P46 airframe continues to have a design flaw which (although perhaps improved) has not been eliminated (based on the MMOPA website and conversations with pilots having similar excursions). The extent of the P46 airframe pilots' concern is evidenced by Piper's customer information letter entitled; 'PA46 Operational & Maintenance Information; Nose Gear Steering.' Would this letter have been issued but for significant continued pilot concern? In its letter; Piper opines that low air pressure in the nose tire and/or a reduction of clearance between the Steering Arm and the Rollers (components of the nosewheel steering system) can contribute to runway excursions. Among other conclusions Piper opines that the air pressure for the nose tire should be 70 psi and that the referenced clearance should be between 0.010 and 0.030 inches with aircraft weight on the wheels. The Mechanic examining my airplane after the excursion rpted 60 psi in the nose gear tire and a clearance of 0.060. The tire had been checked and aired to 70 psi approximately 2 weeks before the excursion. My Piper dealer had completed an annual inspection of the airplane in Sep/08. I am satisfied and I believe Piper is satisfied that such minuscule deviations were not the cause of this excursion; however; I will continue to be extremely cautious that these standards are always met. In conclusion; I am satisfied that there was no pilot error contributing to or causing this excursion. Although I do not have as much time as many pilots; I have landed my Meridian and other airplanes hundreds of times without ever having any experience that even approximates this excursion. From my perspective; the nosewheel steering on my airplane failed. That failure remains of idiopathic origin. I continue to have faith in Piper. Piper has reacted in a responsible manner and I appreciate what it has done and is continuing to do. Perhaps some logical explanation will eventually surface.

Data retrieved from NASA's ASRS site as of May 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.