23.785 Seats, berths, litters, safety belts, and shoulder harnesses
The corresponding rule in CAR 3 is CAR 3.390.
The corresponding airworthiness criteria is section 4.34, Airship Design Criteria, FAA-P-8110-2, Change 2.
Original Issue and Subsequent
a. If a 14 CFR, Part 23 Normal, Utility or Acrobatic airplane is approved as an 11-place airplane, it is acceptable to add an eleventh seat by an FAA Form 337 Field Approval. In this case, the FAA approval must include a placard that reads: “Carriage of more than nine passengers invalidates the Airworthiness Certificate of this airplane.”
b. If a 14 CFR, Part 23 Normal, Utility or Acrobatic airplane is approved as a 10-place or less airplane, addition of seats that permit more than nine passengers by an FAA Form 337 Field Approval is not acceptable. An STC is required to address emergency exit, emergency oxygen, etc. issues. In this case, the FAA approval must include a placard or AFM Supplement limitation that reads: “Carriage of more than 9 passengers invalidates the Airworthiness Certificate of this airplane.”
Methods of Approval of Retrofit Shoulder Harness Installations in Small Airplanes
Special retroactive requirements, § 23.2, is also applicable. A retrofit shoulder harness installation in a small airplane may receive approval either by an STC, field approval, or as a minor change. An STC is the most rigorous means of approval and offers the highest assurance the installation meets all the airworthiness regulations. A field approval is a suitable method of approval for a shoulder harness installation that needs little or no engineering.
The FAA does not encourage the approval of retrofit shoulder harness installations as minor changes. The preferred methods of approval are STC or field approval.
However, the FAA should not forbid the approval of a retrofit shoulder harness installation as a minor change in: 1) the front seats of those small airplanes manufactured before July 19, 1978, and 2) in other seats of those small airplanes manufactured before December 13, 1986.
A retrofit shoulder harness installation may receive approval as a minor change in these small airplanes if:
The installation requires no change of the structure (such as welding or drilling holes).
102 The certification basis of the airplane is either 14 CFR, part 23 before Amendment 23-20, part 3 of the CAR, or a predecessor regulation.
In addition, a minor change installation should follow the guidance for hardware, restraint angles, and attachment locations provided in the following:
AC 43.13-2B, “Acceptable Methods, Techniques, and Practices Aircraft Alterations.”
AC 21-34, “Shoulder Harness-Safety Belt Installations.”
AC 23-19A, “Airframe Guide for Certification of Part 23 Airplanes.”
Installations approved as a minor change may not provide the occupant with the protection required either by regulation (CAR 3.386) or 14 CFR, part 23, § 23.561).
However, a properly installed retrofit shoulder harness installation is a safety improvement over occupant restraint by seat belt alone.
References
AC 21-34, “Shoulder Harness-Safety Belt Installations,” June 4, 1993.
AC 23-19A, “Airframe Guide for Certification of Part 23 Airplanes.” April 30, 2007.
AC 43.13-2B, “Acceptable Methods, Techniques, and Practices—Aircraft Alterations,” March 3, 2008.
Order 8900.1, “Flight Standards Information Management System (FSIMS),” September 13, 2007.
Technical Standard Order (TSO)-C114, “Torso Restraint Systems,” March 27, 1987.
Technical Standard Order (TSO)-C-22g, “Safety Belts,” March 5, 1993.
What are the Requirements?
1. Front seat shoulder harnesses required. Section 23.785 of 14 CFR, part 23, as amended by Amendment 23-19 effective July 18, 1977, required all normal, utility, and acrobatic category airplanes for which application for TC was made on or after July 18, 1977, to have an approved shoulder harness for each front seat. Section 91.205(b)(14) requires all small civil airplanes manufactured after July 18, 1978, to have an approved shoulder harness for each front seat. The shoulder harness must be designed to protect the occupant from serious head injury when the occupant experiences the ultimate inertia forces specified in § 23.561(b)(2). The inertia force requirements are discussed in paragraph 3 below.
2. Shoulder harnesses required at all seats. Section 91.205(b)(16) requires all normal, utility, and acrobatic category airplanes with a seating configuration of 9 or fewer seats, excluding pilot seats, manufactured after December 12, 1986, to have a shoulder harness, for forward-facing and aft-facing seats, that meets the requirements of § 23.785(g) which requires the occupant be protected from the ultimate inertia forces specified in § 23.561(b)(2). Section 23.785(g) also provides the following: “For other seat orientations, the seat and restraint means must be designed to provide a level of occupant protection equivalent to that provided for forward and aft-facing seats with safety belts and shoulder harnesses installed.” Part 91 operating rule stems from § 23.2, Special retroactive requirements, Amendment 23-32, effective December 12, 1985.
3. Belts or harnesses provided for in the design. CAR 3.386 and part 23, § 23.561, Amendments 23-0 through 23-34, effective February 17, 1987, require occupant protection from serious injury during a minor crash landing when “proper use is made of belts or harnesses provided for in the design,” when the occupants are subjected to the following ultimate inertia forces:
Normal and Utility Category Acrobatic Category Forward 9.0g 9.0g Sideward 1.5g 1.5g Upward 3.0g 4.5g
With Amendment 23-36, effective September 14, 1988, the text of § 23.561 quoted above was changed to read: “proper use is made of seats, safety belts, and shoulder harnesses provided for in the design.” Section 23.785(b) was also changed to read:
“Each forward-facing or aft-facing seat/restraint system in normal, utility, or acrobatic category airplanes must consist of a seat, safety belt, and shoulder harness that are designed to provide the occupant protection provisions required in § 23.562 of this part. Other seat orientations must provide the same level of occupant protection as a forward-facing or aft-facing seat with a safety belt and shoulder harness, and provide the protection provisions of § 23.562 of this part.”
The emergency landing ultimate inertia load factors have remained unchanged from Amendment 23-36 through Amendment 23-54, effective December 20, 2000.
Amendment 23-54 is the latest amendment level to part 23.
For inertia force requirements for occupant protection preceding CAR 3, refer to Table 1 in AC 21-34, which lists the requirements for the regulations dating from Bulletin 7-A to the original part 23.
104 What are the methods of approval for retrofit shoulder harness installations?
1. Supplemental Type Certificate (STC). An STC is the most desirable and most rigorous approval. The STC offers the highest assurance that all the airworthiness regulations have been met. The STC approvals are issued by the FAA ACOs. STC approvals are usually obtained by a shoulder harness installation kit supplier for multiple airplane installations in an airplane model or model series.
ACs 21-34 and 23-19A (references 1 and 2 in this section) provide guidance and acceptable means of compliance for shoulder harness and seat belt installations. AC 23-19A specifically addresses part 23 installations. These ACs are also applicable to installations in airplanes having a certification basis of predecessor regulations (for example, CAR 3).
An applicant for an STC may use a salvaged airplane fuselage to substantiate the strength of the fuselage and the shoulder harness attachment fittings by structural tests, since the shoulder harness attachment structural test may damage an airworthy fuselage. It may be a problem that the available test airframe may be stronger than the lowest strength production airframe. This may be a problem in steel tube airframes.
During many years of producing such airframes, various specification materials may have been used. For example, many CAR 3 (and predecessor regulations) airplanes were originally produced from 1025 steel tubing and later constructed from higher strength 4130 steel. In one case studied, two different specification 1025 steel tubes were used which may have an Ultimate Tensile Strength (UTS) ranging from 55,000 to 79,000 Pounds Per Square Inch (PSI). The UTS of 4130 steel is 90,000 to 95,000 PSI.
The test article should be representative of the lowest strength production airframe.
This may be accomplished by a conformity inspection using the production drawings.
The strength of materials of parts affected by the modification needs to be verified by the airframe manufacturers process and production records. The serial number of the test article needs to be verified.
An alternative course of action would be to determine, by appropriate tests (for example, chemical analysis, hardness tests, and strength tests), the strength of the parts of the test article affected by the modification. Follow with testing to a conservatively higher load that accounts for the difference in strengths of the test article and the lowest strength production article. Determination of the higher applied test load should consider any uncertainty in the test(s) used to determine the strength of the material.
Another alternate course of action may be to conduct the harness pull test on the available test airframe. The applicant may then substantiate the strength of other tubing specifications by a combination of test results and analysis.
105 AC 23-19A provides an acceptable means of compliance for static strength substantiation of attachment points for occupant restraint system installations. A test block is described to apply the 9.0-g forward inertia load. The safety belt installation alone is tested to 100 percent of the load. The shoulder and safety belt combined load is distributed 40 percent to the shoulder harness and 60 percent to the seat belt.
In airplanes having side-by-side seats, the pull test may need to be applied simultaneously to the harness fittings for both seats. However, this depends on the type of harness and where the upper ends are anchored. Normally, this would not be necessary for a single diagonal belt shoulder harness attached to the outboard fuselage side or wing spar root end.
In a pull test for a retrofit shoulder harness installation in a tandem seated tubular steel fuselage, the forward inertia load was applied simultaneously for both harnesses.
This was done for convenience in applying and reacting the loads. It was found, that because of the tube geometry, the load at the aft harness attachment caused a tension in the rear spar carry through tube. The front seat shoulder harness upper end was attached to the rear spar carry through tube. This enabled the front seat harness attachment to test to a higher load than if the pull test was done to each harness individually. In such a case, the test loads for each harness should be done individually.
Part 21, § 21.50(b) requires the holder of an STC to provide instructions for continued airworthiness, prepared in accordance with § 23.1529.
An STC cannot be used to modify an aircraft without the permission of the STC holder. 14 CFR, part 21, § 21.120, requires the STC holder to provide the customer (installer or airplane owner) with a signed permission statement when the STC is used for compliance that includes:
1. product (aircraft, engine, pr opeller, or appliance) to be altered, including serial number of the product;
2. the STC number; and
3. the person(s) who is being gi ven consent to use the STC.
The permission statement needs to be kept as part of the aircraft records. The requirement for this permission statement originated in the Federal Aviation Authorization Act of 1996 (Public Law 104-264). This provision was put into law to try to stop the pirating of STCs.
2. Field Approval. A shoulder harness installation in a small airplane may receive a field approval (FAA Form 337) granted by a Flight Standards ASI. Field approvals are appropriate for alterations that involve little or
106 no engineering. If the installation requires structural modifications, an ACO will need to help in the field approval process by approving the structural aspects of the installation. In that case, a field approval constitutes a change to type design and must meet the same regulatory requirements as an STC.
AC 43.13-2B (reference 3 in this section) contains methods, techniques, and practices acceptable to the Administrator for use in altering civil aircraft. Chapter 9 covers shoulder harness installations. Section 3 covers attachment methods. Shoulder harnesses installed under field approval must meet the same regulatory requirements as an STC; therefore, the applicant should show by test 9.0-g forward load capability.
Field approvals for shoulder harness installations should not be done by referencing a previous field approval and deleting the pull test, unless the attachment parts either have a PMA, or other FAA approval. If the attachment parts have no FAA approval, the strength is not known or assured, since they have not been manufactured to an FAA approved quality control system.
Shoulder harness installations attaching to the center of an unsupported wing carry through tube, or other unsupported member, should not receive a field approval without a design approval from an ACO. Applying the test load in such cases may cause damage or permanent set to the affected structure.
Existing FAA guidance, including AC 43.13-2B and AC 21-34, recommend against attachment to the center of unsupported members. Figure 9-16 in AC 43.13-2B shows typical shoulder harness attachments to tubular members. These are all at tube intersections and not at the center of unsupported tubes.
Figure 9-14 in AC 43.13-2B shows a typical wing carry through member installation.
This is in the center of the carry through member that is a hat section as found in metal skinned airplanes. Part of the figure shows the hat section is riveted to sheet metal skin (which would provide longitudinal support
Personnel performing the field approval must assure that both the harness and belt are compatible and have a TSO approval, or
1. have been produced under a PMA, or
2. other compliance means appropriate to the certification basis of the aircraft.
3. Minor change. Part 21, § 21.93(a), Classification of changes in type design, states as follows: “A minor change is one that has no appreciable effect on the weight, balance, structural strength, reliability, operational characteristics, or other characteristics affecting the airworthiness of the product.”
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107 Information provided to us by the Anchorage ACO suggests that some shoulder harness installations that provide known safety improvements have been approved as a minor change. In these situations, the FAA certificated mechanic who installs it makes an entry in the maintenance log of the airplane. One shoulder harness installation kit supplier uses this process (no FAA approvals) to install shoulder harnesses in PA-18 airplanes. The installation does not require modification of the airframe. The front seat harness attaches to the center of the rear wing spar carry through tube. However, it may not meet the 9.0-g forward inertia load required by CAR 3.386. The kit supplier stated that some airplane owners who had accidents reported the harness installation had saved their lives.
In general, shoulder harness installations should not use the center of an unsupported wing carry through tube or other unsupported member as an attachment point. This type of attachment may pose a risk to the structural integrity of the airplane.
Although the attachment may be a clamp-on fitting that does not alter the existing airframe, the installation may result in a major change in the type design. This is because the shoulder harness attachment may introduce new loading conditions into the carry through tube.
It is acceptable for the carry through structure to be damaged in an emergency landing. However, it is unacceptable for the tube to fail in-flight. Carry through tubes, loaded in compression, may experience a beam-column buckling failure if the occupant applies a load to the shoulder harness attachment. Occasionally, small loads on the shoulder harness attachment may cause beam-column buckling failures.
Some shoulder harnesses that have been installed by minor change do not have a TSO approval. TSO-C114, Torso Restraint Systems, was issued March 27, 1987. Torso restraint systems manufactured before that date did not have to meet the prescribed SAE standard, Aerospace Standard 8043B, “Restraint Systems for Civil Aircraft,” dated September 12, 2008. AC 43.13-2B and AC 21-34 provide guidance for acceptable harnesses. Acceptable harnesses for minor change installations include:
1. harnesses that meet TSO-C114 or Military Specification (MIL-SPEC) requirements,
2. harnesses that have been produced under a PMA, or
3. other harnesses appropriat e to the certification basis of the aircraft.
FAA has studied the circumstances of shoulder harness installations done by minor change. An airplane owner may wish to install shoulder harnesses, but an STC or prior field approval is not available for his airplane. In this case, it is not likely that an individual airplane owner would apply for an STC or a field approval since the owner would need to hire an engineering consultant to perform
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108 the structural test and any associated structural analysis. Also, there is a possibility the airframe may be damaged during the pull test. In such installations, a pull test would not be done and there is no assurance the installation will provide occupant protection to the ultimate inertia force requirements (the 9.0-g forward force) of § 23.561 or CAR 3.386.
About the installation of shoulder harnesses by minor change, FAA concludes the following: Since CAR 3.386 and § 23.561(b)(1) before Amendment 23-36 (which became effective September 14, 1988) state that “proper use is made of belts or harnesses provided in the design,” the previously approved seat belt installation alone must meet the prescribed ultimate inertia forces.
CAR 3.652, Functional and installation requirements, states as follows: “Each item of equipment which is essential to the safe operation of the airplane shall be found by the Administrator to perform adequately the functions for which it is to be used, shall function properly when installed, and shall be adequately labeled either for identification, function, operational limitations, or any combination of these, whichever is applicable.”
Before Amendment 23-20 (which became effective September 1, 1977), § 23.1301 contained essentially the same requirement as CAR 3.652. Amendment 23-20 deleted the words “essential to safe operation” and made the provisions of § 23.1301 applicable to “each item of installed equipment.”
FAA concludes from these rules that if a shoulder harness is not required equipment, it is not essential to the safe operation of the airplane. Therefore, CAR 3.652 and § 23.1301, before Amendment 23-20, should not be used as a basis to prohibit shoulder harness installation by minor change. These rules should be applied to shoulder harness installations made by STC and field approval.
The mechanic making such installations should consult AC 43.13-2B, Chapter 9, for information on restraint systems, effective restraint angles, attachment methods, and other details of installation.
See AC 21-34, “Shoulder Harness-Safety Belt Installations,” AC 21-25A, “Approval of Modified Seats and Berths,” and AC 43.13-2B, “Acceptable Methods, Techniques, and Practices—Aircraft Alterations.”
Aft-facing and side-facing seats
For aft-facing seats, seat obliqueness should be limited to 15 degrees unless additional occupant protection for side-facing seats is installed.
Part 23 allows side-facing seats, but it does not address the crashworthiness problems of these installations. FAA recommends that side-facing seat installations be
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109 discouraged. If such an installation is made, the following should be applied as well as any applicable rules from the original certification basis:
a. A sideward facing seat is defined as one in which the plane of symmetry of the occupant makes more than an 18 degrees angle with the vertical plane containing the airplane centerline when viewed from above.
b. Each occupant of a sidewa rd facing seat should be protected from serious head injury when experiencing the inertia forces of § 23.561(b)(2) by both a safety belt and energy absorbing rest that will support the head and torso or by a safety belt and shoulder harness that will prevent the head from contacting any injurious object. There should be adequate padding on any restraining bulkhead. Riding up of diagonal shoulder straps on the neck, which could cause neck injury, and location of attachments and rigidity of the seat support that could cause twisting and compression of the spine should be considered. For a multiple side-facing seat, a passenger seated immediately forward of another passenger cannot be considered an energy absorbing rest (human cushion).
c. Sideward facing seat installations that do not comply with paragraph “b” above should be placarded to prohibit occupancy during takeoff and landing. The sidefacing seats still require one seat belt for each passenger to protect against inflight turbulence, and the berth should be considered an item of mass for emergency landing conditions of § 23.561.
d. Special conditions will be required for sideward facing seats that are to be occupied during takeoff and landing when the certification basis requires compliance with § 23.562, Emergency landing dynamic conditions.
Seat Removal for Parachute Operations
This guidance is intended for engineering assistance in the field approval process, TC approval or STC approval of sport parachute modifications to small airplanes. The Small Airplane Directorate has received NTSB recommendations on the safety record of small airplanes that have been modified for use in sport parachute operations.
Most of these modifications have been approved by FAA Form 337 field approvals without engineering assistance. These modifications should either be approved by the TC process, STC process or by a field approval with engineering assistance. ACOs should not provide engineering assistance for sport parachute modifications that change the limitations of an airplane or affect primary structure, required systems and equipment, handling, crashworthiness or performance. They should be completed using an STC or TC.
The acceptability of sport parachute operations is given in operational regulations.
14 CFR, part 91, allows the use of the cabin floor for sport parachute operations and requires the operations be conducted per 14 CFR, part 105. Part 105 requires radio equipment for operations in controlled airspace, but there are no other equipment
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110 requirements other than the parachutes. AC 105-2C, “Sport Parachute Jumping,” gives information on complying with the regulations and provides a list of airplanes that may be operated with one cabin door removed. The part 91 regulation means floor seating is acceptable only for sport parachute operations, but this does not mean the crashworthiness of the airplane can be unacceptable or that an unsafe condition can be created by a modification.
The small airplane certification basis is mostly CAR 3 or early part 23. The modifications include: seating capacity increases, seat and restraint removal and replacement belt installation, door removal for airplanes not listed in AC 105-2C, step and hand holds on airplane exteriors, gross weight increases and CG changes.
Seating capacity increases can be acceptable if: 1) all people are protected in emergency landing loads per § 23.561 (3.386), 2) all persons are secured against sliding backwards in climbs to maintain an acceptable CG position, and 3) any changes in allowable CG range and increased gross weight are found acceptable. The applicant should also supply data to show that emergency exits are not crowded in a ground evacuation with the increased seating capacity per § 23.807 (3.387). This test/analysis must be done with all occupants except one representing a pilot in a parachute, and all parachutists initially restrained in place by the replacement belts/restraints.
Removal of certified seats, seat belts and shoulder harnesses, if any, is allowable per part 91, § 91.207(a)(3)(ii). This does not remove the requirement to prevent an unsafe condition in an emergency landing or normal operations. The replacement belts/restraints should, therefore, meet the requirements for emergency landing upward, forward and sideward loads, per § 23.561 (3.386), and secure all people against sliding backwards in climbs to maintain an acceptable CG position. Per § 23.785 (3.390), the attachment of the replacement belts/restraints to structure must have a factor of 1.33 times the emergency landing loads in § 23.561 (3.386). A simple belt that fastens across the lap of a person sitting on the cabin floor is not acceptable.
This prevents movement only in the direction the person is facing. For instance, facing to the rear (as has been reported) prevents movement toward the tail in a climb, but it does not secure a person against uncontrolled movement toward the front in an emergency landing. The FAA and the United States Parachute Association (USPA) have tested a pair of adjustable belts attached to the parachute harness and found that they are more effective in providing restraint while the emergency-landing forces dissipate. FAA finds it acceptable, therefore, for a parachutist to use adjustable belts instead of the seat belt. Acceptable restraint systems for floor seating of sport parachutists are given by the Civil Aeromedical Institute (CAMI) of the FAA in Report DOT/FAA/AM-98/11, “Evaluation of Improved Restraint Systems for Sport Parachutists,” dated March 1998. The dual-strap restraints (5D, 6D and 7D) provided the least flailing and bending of body segments and the least forward translation of the pelvis. ACOs should require one of these restraint systems for any TC, STC or
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111 engineering assistance to a field approval. Limitations should be imposed to call out the three operational procedures on page 21 of the CAMI Report.
The dual strap restraints have been tested with floor attachments. So far, there has not been any acceptable testing of a sidewall attachment. An applicant who wants to attach a restraint system to a sidewall will need to perform sled testing by an approved procedure to verify its relevance in the emergency landing loads.
An acceptable procedure for use of the dual-strap restraints (5D, 6D and 7D) is as follows:
a. Sit on the aircraft floor between two seat rails facing aft.
b. Attach two adjustable belts to your parachute harness for the 5D, 6D, or 7D configuration. You may loop the adjustable belt through your parachute harness webbing or you may attach a quick-release clip through the ring on your harness.
c. Attach the other end of each harness to the seat rail in the aircraft floor. Make the attachment to the floor rail on the same side as the attachment to your harness.
d. Adjust the belt as snugly as possible without causing discomfort.
NOTE: If possible, place a lap belt attached to the floor rails around your upper legs to prevent flailing during the emergency landing.
Door removal raises issues in Subpart B of 14 CFR part 23. Performance, stability, and control must be found acceptable with the door removed in flight. If the AFM gives performance numbers such as takeoff and takeoff over a 50-foot obstacle, the applicant should verify that performance or issue a Flight Manual Supplement (FMS) with the revised numbers. Of course, the applicant does not have to present any data or do any tests for airplanes that are listed in AC 105-2C.
Steps and handholds to be installed on the exterior of a small airplane should be shown to meet the structural strength and fatigue requirements in part 23 (CAR 3).
Carriage of parachutists outside the aircraft must be shown to not be hazardous in a power loss failure in takeoff and climb flight phases.
Increases in gross weight and allowable CG range should be shown to comply with the requirements in part 23 (CAR 3) as would any other modification that affected these numbers.
Aircraft modified for sport parachute operation must include a placard or flight manual limitation that prohibits flight with doors or seats removed except in sport parachute operation.
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112 Amendment 23-7 and Subsequent This amendment adopted a proposed revision in NPRM 67-14 that stated:
“Experience indicates that a significant reduction in injuries and fatalities in small airplane accidents may be obtained by the installation and use of effective upper body restraints or by designing airplane interiors to either eliminate injurious objects within striking radius of the head or provide energy absorbing support for the upper torso. This proposal would therefore apply, to small airplanes, standards identical with those long administered for large airplanes under Sec. 25.785(c).”
AC 23-28, when issued, will provide information and guidance applicable to the static strength substantiation of the attachment points for occupant restraint system installations, which have both a safety belt and shoulder harness.
Amendment 23-36 and Subsequent This amendment adopted a proposed revision to NPRM 86-19 that stated: “The FAA is proposing a substantial revision of the current and new requirements for seats, berths, litters, safety belts, and shoulder harnesses. The revision is considered necessary to present the proposed requirements in a more logical sequence as a result of the new requirements being proposed by this rulemaking action. The new requirements are based to a large extent on the proposals submitted by the GASP to the Part 23 Airworthiness Review Program. The GASP proposals were based in large measure on FAA, NASA, and NTSB research studies and impact/accident analyses.”
See guidance for § 23.562, Emergency landing dynamic conditions.
See guidance for dynamic seat certification in AC 20-146, “Methodology for Dynamic Seat Certification by Analysis for Use in Part 23, 25, 27, and 29 Airplanes and Rotorcraft.”
Part 23 did not envision more than two seats on the flight deck, although the part does not prohibit such an installation. The airworthiness standards do not contain adequate standards for an “observer” seat (occupied by an FAA Flight Standards inspector on commuter flights). Therefore, FAA would expect to apply special conditions to such an installation that would address occupant restraint, emergency egress, and appropriate placarding to prohibit use by a passenger under any circumstances. The special conditions should establish a level of safety equivalent to that established in the certification basis of the airplane. This is not only for the observer seat occupant but also the crewmember seated in front of the occupant.
The weight of a parachute is included in the 215-pound occupant weight if a parachute is required. The weight remains at 215 pounds when a parachute is not required.