Airworthiness Directive · Amendment 39-14723 · GROB-WERKE GMBH & CO KG Model G102 ASTIR CS Sailplanes
GROB-WERKE GMBH & CO KG Model G102 ASTIR CS Sailplanes
This AD affects Model G102 ASTIR CS sailplanes, serial numbers 1001 through 1536, that are certificated in any category.
The FAA supersedes Airworthiness Directive (AD) 84-09-05, which applies to certain GROB-WERKE GMBH & CO KG (previously identified as BURKHART-GROB FLUGZEUGBAU INDUSTRIESTRABE) Model G102 ASTIR CS sailplanes. AD 84-09-05 requires you to install a modified spherical locking bolt and nut in the forward horizontal stabilizer connection to the vertical stabilizer and install new locking pins in the aft connecting plate for the horizontal stabilizer. Since we issued AD 84- 09-05, fatigue cracks were found in the modified spherical locking bolt. Consequently, this AD requires you to replace the modified spherical locking bolt, the retaining pins (collar bolts), and associated hardware; add a life limit on the spherical locking bolt and the retaining pins; and repetitively inspect the front and rear horizontal stabilizer attachment. This AD results from mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. We are issuing this AD to prevent cracks in the spherical locking bolt, which could result in failure of the horizontal stabilizer connection. This failure could lead to loss of control.
To address this problem, you must do the following:
| Actions | Compliance | Procedures |
|---|---|---|
| (1) Remove and replace as follows: | ||
| (i) Remove the existing retaining pins (collar bolts) and the self-locking nut and replace with new retaining pins, part numbers (P/N) 102-2142.46, and self-locking nut, P/N LN9348-M8 (or FAA-approved equivalent part numbers), on the T-plate; (ii) Remove the existing spherical locking bolt and replace with a new spherical locking bolt, P/N 102-3500.21, that has revision letter “b” permanently marked on the bottom of the bolt (or FAA-approved equivalent part number). Return replaced spherical locking bolts, P/N 102-3500.21, to Grob Systems, Inc., Aircraft Division, 1070 Navajo Drive, Bluffton, Ohio 45817; | Within the next 90 days after September 22, 2006 (the effective date of this AD), unless already done. After doing the replacements, the spherical locking bolt and the retaining pins have a life limit of 10 years and must be replaced at that time | As specified in GROB Service Bulletin MSB306-38/1, dated November 28, 2005, following the Accomplishment Instructions in GROB Service Bulletin MSB306-38, dated February 12, 2004, and the Annual Inspection procedures on pages 7 and 8 of the Astir CS Maintenance Manual, Rev. 9, dated Nov. 2005. |
| (iii) Remove the existing nut and replace with a new nut, 102-3510.21 (or FAA-approved equivalent part number); and | ||
| (iv) Remove the existing lock washer and replace with a new lock washer, P/N DIN 6797-10,5PHR (or FAA-approved equivalent part number) | ||
| (2) Using a dye-penetrant method along with a minimum 10X magnifying glass, repetitively inspect the front and rear horizontal stabilizer attachment assembly for excessive movement, cracks, and/or damage in the spherical locking bolt. This inspection method takes precedence over the procedures outlined in GROB Service Bulletin MSB306-38, dated February 12, 2004 | Initially inspect within the next 100 hours time-in-service (TIS) or at the next annual inspection after the replacement required in paragraph (e)(1) of this AD, whichever occurs first. Repetitively inspect thereafter at 12-month intervals or at intervals not to exceed 100 hours TIS, whichever occurs first | As specified in GROB Service Bulletin MSB306-38/1, dated November 28, 2005, following the Accomplishment Instructions in GROB Service Bulletin MSB306-38, dated February 12, 2004, and the Annual Inspection procedures on pages 7 and 8 of the Astir CS Maintenance Manual, Rev. 9, dated Nov. 2005. |
| (3) If, during any inspection required in paragraph (e)(2) of this AD, you find excessive movement: | ||
| (i) In the front horizontal stabilizer attachment, you must replace the spherical locking bolt with a new part. | Before further flight after each inspection required in paragraph (e)(2) of this AD. After each replacement, the spherical locking bolt and the retaining pins have a life limit of 10 years and must be replaced at that time | As specified in GROB Service Bulletin MSB306-38/1, dated November 28, 2005, following the Accomplishment Instructions in GROB Service Bulletin MSB306-38, dated February 12, 2004, and the Annual Inspection procedures on pages 7 and 8 of the Astir CS Maintenance Manual, Rev. 9, dated Nov. 2005. |
| (ii) In the rear horizontal stabilizer attachment, you must replace the retaining pins with new parts | ||
| (iii) In the front and rear horizontal stabilizer attachment after doing the replacement(s) required in paragraph (e)(3)(i) and (e)(3)(ii) of this AD, you must replace the bearings in the stabilizer spar web | ||
| (4) If, during any inspection required in paragraph (e)(2) of this AD, you do not find excessive movement in the front and rear horizontal stabilizer attachment: | ||
| (i) Inspect the spherical locking bolt for cracks and damage using a dye-penetrant method along with a minimum 10X magnifying glass (ii) If you find cracks or damage on the spherical locking bolt, during the inspection required in paragraph (e)(4)(i) of this AD, you must replace the bolt with a new bolt | Before further flight after each inspection required in paragraph (e)(2) of this AD. After each replacement, the spherical locking bolt and the retaining pins have a life limit of 10 years and must be replaced at that time | As specified in GROB Service Bulletin MSB306-38/1, dated November 28, 2005, following the Accomplishment Instructions in GROB Service Bulletin MSB306-38, dated February 12, 2004, and the Annual Inspection procedures on pages 7 and 8 of the Astir CS Maintenance Manual, Rev. 9, dated Nov. 2005. |
| (5) Do not install any spherical locking bolt, P/N 102-3500.21 (or FAA-approved equivalent part number), that does not have revision letter “b” permanently marked on the bottom of the bolt | As of September 22, 2006 (the effective date of this AD) | Not applicable. |
| (6) 14 CFR 21.303 allows for replacement parts through parts manufacturer approval (PMA). The phrase “or FAA-approved equivalent part number” in this AD is intended to signify those parts that are PMA parts approved through identicality to the design of the part under the type certificate and replacement parts to correct the unsafe condition under PMA (other than identicality). If parts are installed that are identical to the unsafe parts, then the corrective actions of the AD affect these parts also. In addition, equivalent replacement parts to correct the unsafe condition under PMA (other than identicality) may also be installed provided they meet current airworthiness standards, which include those actions cited in this AD | Not applicable | Not applicable. |
Note: During ground handling, it has been noted that a tendency exists for the ground crew to move these gliders by using the horizontal stabilizer as a lifting point. This practice may facilitate damage to the stabilizer assembly and should be avoided. See Caution note in GROB Service Bulletin MSB306-38, dated February 12, 2004.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
