C425 pilot reported a brake failure on landing that resulted in a runway excursion.

Narrative:

Loss of right side brakes after landing. Upon landing roll out at the end prior to the turn; the plane started to drift left on runway xyr; as the plane slowed down and rudder authority was lessened the attempt to correct the drift required slight braking to correct. When the brake was applied there was no braking action. Throttles were in beta to slow the plane down to make the turn off at the end of the runway. The plane eventually spun 360 degrees with the left wheel going into the grass. Once stopped (facing the correct direction) an attempt to use differential throttle an/or beta and propeller pitch to clear the runway the plane spun around a second time. The gust crosswind was making control without the use of the brakes difficult. Managed to move off the runway onto the taxiway; but still not clear of the hold short line; the plane proved to difficult to control on the ground in the wind without the brake functioning. Advised tower the plane was inoperable and needed assistance. ZZZ had to open runway xxl which was closed by NOTAM (notice to airmen); and close runway xyr as I was unable to clear the runway. The controller was extremely helpful; as well as the operations personnel at the airport.despite at least one main wheel going into the grass and the chance of contacting light fixtures; it was all avoided. No damage to the plane; runway lights; or injury.

Original NASA ASRS Text

Title: C425 pilot reported a brake failure on landing that resulted in a runway excursion.

Narrative: Loss of right side brakes after landing. Upon landing roll out at the end prior to the turn; the plane started to drift left on Runway XYR; as the plane slowed down and rudder authority was lessened the attempt to correct the drift required slight braking to correct. When the brake was applied there was no braking action. Throttles were in beta to slow the plane down to make the turn off at the end of the runway. The plane eventually spun 360 degrees with the left wheel going into the grass. Once stopped (Facing the correct direction) an attempt to use differential throttle an/or Beta and Propeller pitch to clear the runway the plane spun around a second time. The gust crosswind was making control without the use of the brakes difficult. Managed to move off the runway onto the taxiway; but still not clear of the hold short line; the plane proved to difficult to control on the ground in the wind without the brake functioning. Advised Tower the plane was inoperable and needed assistance. ZZZ had to open Runway XXL which was closed by NOTAM (Notice to Airmen); and close Runway XYR as I was unable to clear the runway. The controller was extremely helpful; as well as the operations personnel at the airport.Despite at least one main wheel going into the grass and the chance of contacting light fixtures; it was all avoided. No damage to the plane; Runway lights; or injury.

Data retrieved from NASA's ASRS site 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.

Attributes
ACN	1707468
Time
Date	201912
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	Marginal
Light	Daylight
Aircraft 1
Make Model Name	Cessna 425/441 Conquest I/Conquest II
Operating Under FAR Part	Part 91
Flight Phase	Landing
Route In Use	Visual Approach
Flight Plan	IFR
Component
Aircraft Component	Normal Brake System
Person 1
Function	Single Pilot Pilot Flying
Qualification	Flight Crew Private Flight Crew Multiengine Flight Crew Instrument
Experience	Flight Crew Last 90 Days 16 Flight Crew Total 782 Flight Crew Type 247
Events
Anomaly	Aircraft Equipment Problem Critical Ground Event / Encounter Loss Of Aircraft Control Ground Excursion Runway