Narrative:

Please be advised; the statements made; specifically 'we now have the capability to download data from aircraft through ACARS to calculate the aircraft to runway friction value' may relay a concept that is not supported. The intended function of inferring an aircraft braking level through captured data in a manner that corresponds to the guidance as outlines in AC 25-32; 91-79A; and 150/5200-30D has not been proposed to the FAA by aviation safety technologies any formal means such as stc; opspec; or any other manner. To date the only entity to apply for certification of such a function does not produce the 737-series model. For the FAA; please note there is no means for this airline to validate stc certification; tso (technical standard order) compliance; and pma (parts manufacturer approval) compliance; find compliance with an opspec; nor is there any means within flight standards to review and accept any intended function where aircraft data can be shown to comply with any standard relating to this type of function. Furthermore; even with an 'NTSB style analysis;' done with the cooperation of the oem; there is no standard for relating the time varying wheel braking coefficient data to an industry accepted standard for could map such data to the outcomes of the equations from far 25.109C and other non-groundspeed dependent values in AC 25-32.I would advise the company that the risk and resource management model currently being taught is based on functions; methods; and procedures that have been either certified or approved by the FAA in the manner referred to above. Industry and standards organizations are currently addressing this issue. However; no consensus has to date been reached and no standards; advisory circulars; opspecs; policy letters; or orders have been published by the FAA addressing this function. Furthermore; the FAA does not publish a definition of a pilot braking action report in the aim. While AC 91-79A does give 'vehicle braking' descriptions; these do not cover the important concepts such as friction limited braking vs torque limited braking; performance critical landings; nor offer techniques for which a pilot may discriminate and observe these issues. Again; this issue has been addressed by the society of aircraft performance and operations engineers (sapoe) in conjunction with the american society of materials and standards (astm). However; no official guidance has been accepted by FAA flight standards to date.I would recommend changing the verbiage to the following: we are currently in the process of doing company research involving a potential method for calculating aircraft braking levels with aviation safety technologies. These methods are not approved by the FAA and may not represent actual braking performance; however; we feel there is value in comparing the output of this system to the observations of the flight crew if there is any desire to learn more about this; please feel free to have the appropriate administrator facilitate communications between myself and or company and I will be happy to assist and advise.

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Original NASA ASRS Text

Title: B737 pilot reported that the capability to download data from aircraft through ACARS to calculate the runway friction value may rely on a concept that is not supported.

Narrative: Please be advised; the statements made; specifically 'We now have the capability to download data from aircraft through ACARS to calculate the aircraft to runway friction value' may relay a concept that is not supported. The intended function of inferring an aircraft braking level through captured data in a manner that corresponds to the guidance as outlines in AC 25-32; 91-79A; and 150/5200-30D has not been proposed to the FAA by Aviation Safety Technologies any formal means such as STC; OpSpec; or any other manner. To date the only entity to apply for certification of such a function does not produce the 737-series model. For the FAA; please note there is no means for this airline to validate STC certification; TSO (Technical Standard Order) compliance; and PMA (Parts Manufacturer Approval) compliance; find compliance with an OpSpec; nor is there any means within Flight Standards to review and accept any intended function where aircraft data can be shown to comply with any standard relating to this type of function. Furthermore; even with an 'NTSB style analysis;' done with the cooperation of the OEM; there is no standard for relating the time varying wheel braking coefficient data to an industry accepted standard for could map such data to the outcomes of the equations from FAR 25.109C and other non-groundspeed dependent values in AC 25-32.I would advise the Company that the risk and resource management model currently being taught is based on functions; methods; and procedures that have been either certified or approved by the FAA in the manner referred to above. Industry and standards organizations are currently addressing this issue. However; no consensus has to date been reached and no standards; advisory circulars; OpSpecs; Policy Letters; or Orders have been published by the FAA addressing this function. Furthermore; the FAA does not publish a definition of a Pilot Braking Action report in the AIM. While AC 91-79A does give 'vehicle braking' descriptions; these do not cover the important concepts such as friction limited braking vs torque limited braking; performance critical landings; nor offer techniques for which a pilot may discriminate and observe these issues. Again; this issue has been addressed by the Society of Aircraft Performance and Operations Engineers (SAPOE) in conjunction with the American Society of Materials and Standards (ASTM). However; no official guidance has been accepted by FAA Flight Standards to date.I would recommend changing the verbiage to the following: We are currently in the process of doing Company research involving a potential method for calculating aircraft braking levels with Aviation Safety Technologies. These methods are not approved by the FAA and may not represent actual braking performance; however; we feel there is value in comparing the output of this system to the observations of the Flight Crew If there is any desire to learn more about this; please feel free to have the appropriate administrator facilitate communications between myself and or Company and I will be happy to assist and advise.

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.