Flight Safety, Primary, and Critical Parts

Bell is committed to providing safe and reliable aircraft to help customers accomplish their missions. That’s why we have the Flight Safety Parts Program, to help ensure the critical elements of flight-essential parts are consistently produced and maintained with defined engineering limits throughout their life cycle.

Flight Safety Parts

Requirements of this program are detailed in Bell Specification 299-947-478 Flight Safety Parts Program. Suppliers must adhere to these requirements when the Bell Engineering Drawing states that the part is designated as a Flight Safety Part. The BHT drawing shall contain the FSP Decal and Critical Characteristic Symbol (Diamond with the letter C inside).

A Flight Safety Part (FSP) is defined as any part, assembly, or installation whose failure, malfunction, or absence could cause loss of or serious damage to the aircraft and serious injury or death to the occupants or ground support personnel. FSP's may include detail parts, assemblies, or installations depending upon the drawing level at which the part obtains a critical characteristic. BHT may designate as FSP only those parts identified by part numbers resulting from BHTI drawings/dash numbers. This includes parts depicted on Control Drawings (Source or Specification Drawings). The responsible supplier designates Flight Safety Parts and identifies critical characteristics on part numbers resulting from supplier drawings other than parts on BHT Control drawings subject to approval by BHT Engineering. Standard attachment hardware shall not be classified as FSP's, but may be designated as critical characteristics, when applicable, on assemblies and installations designated FSP. All FSP's shall have at least one critical characteristic.

A critical characteristic is any feature, throughout the life cycle of a FSP, which if non-conforming, missing, or degraded, could cause failure or malfunction of the FSP. Critical characteristics include dimension, tolerance, finish, material, assembly, manufacturing and inspection processes. The life cycle shall cover manufacture, operation, field maintenance, and overhaul of the FSP.

Critical Parts

The purpose of the Bell Helicopter Critical Parts Program is to provide procedures and controls necessary to attain the high reliability required for specific parts designated as Critical Parts or "Makes a Critical Part". Bell Helicopter Operating departments and subcontractors, suppliers of BHT designed parts, and suppliers of supplier designed parts shall implement the requirements and procedures contained in BHT Specification 299-099-796 Critical Parts Program Requirements Specification. Critical Parts are non-redundant and in which a failure would result in a condition that would inhibit or prevent a safe landing. As a minimum, all rotor system components such as the mast, main and tail rotor blades, parts located in the main and tail rotor hubs, and the rotating controls will be classified as Critical Parts; however, such hardware may be subject to special inspection requirements. A detail part contained in an assembly designated as critical will not itself be considered critical unless designated critical as a Detail Part. Likewise, an assembly containing critical detail parts will not itself be considered critical unless so designated. A part designated critical must have at least one characteristic designated either significant or critical. Makes-A-Critical Part is defined as a casting, forging, or composite part that is utilized to make a critical part. A Makes-A-Critical Part requires traceability to the Critical Part. Traceability records must be permanently maintained.

All Critical, Makes-A-Critical part, and the applicable next assembly shall be serialized in order to ensure required traceability. Installations do not require serialization. Suppliers of Critical or Makes-A-Critical, which have been designed by BHT, shall be subject to special control measure imposed by Quality procurement. The supplier of supplier designed parts shall be responsible for the implementation of all requirements of 299-099-796, inclusive of the intent of paragraph 3.8.1, items a through f. Quality procurement requirements shall include special control measures for Critical Parts schedules for manufacture by suppliers of supplier designed parts.

Primary Parts

Primary Parts are those parts which require special Product Assurance controls. Generally, Primary Parts are those for which structural integrity is essential for the safety of the aircraft and the failure of which would result in forced landing of the aircraft.

All Primary Parts suppliers shall be qualified QPS 100, QPS 102 and 299-947-140 by BHT Product Assurance. Acceptable first article demonstrations will include necessary destructive laboratory testing to evaluate, as applicable, the chemical, physical, and metallurgical properties which have been established as design requirements. Also to be included in the qualification procedure is the creation of Primary Part Planning (known as "Frozen Planning"). Suppliers must be qualified to be approved for the Primary Parts Program by submitting a first article and approved in like manner. Suppliers to be approved for Primary Parts shall be deleted from the approved list after 12 consecutive months of inactivity, unless Procurement notifies Product Assurance that such activity is pending. BHT approved suppliers/processors shall remain active provided services have been performed on any classified part (Primary, Critical, or Flight Safety) within the previous 12 consecutive months.

Supplier facilities and quality system shall be surveyed for the applicable requirements and shall be established and enforced by product assurance department. The Product Assurance Department will conduct an annual survey of each facility that produces BHT Primary Parts. The survey shall include a review of the supplier's quality system. Certain Primary Parts, when identified by BHT Engineering, shall be traceable backward to the specific lot of material and forward to the aircraft in which they are installed.

Any sub-tier supplier performing critical operations on a Primary Part is subject to the audit and approval criteria set forth by Bell Helicopter Supplier Quality Assurance prior to starting work. Sub-tier suppliers of processes that are critical characteristics must be surveyed, approved and identified in the Bell Helicopter "Approved Source List for Special Processes and Laboratories".

Engineering or Specification Changes Suppliers requesting changes to the BHT Engineering Drawings and/or Specification shall submit a Supplier Information/Action Request (SIAR) to your appropriate Buyer. Bell in turn reviews the request and dispositions the request as approved or disapproved. If approved, Bell Helicopter Engineering will revise the document in accordance with your request. A newly revised document will then be sent.

If disapproved, you will be notified in writing with the rationale used for the disapproval.