# N721RC: 2015 Alexander Schleicher ASK 21 - Status: Valid registration - Airframe: [Alexander Schleicher ASK 21](https://openairdocs.org/model/alexander-schleicher-ask-21) (registry code 3801539, 2 seats) - Engine: [NONE](https://openairdocs.org/engine/none) (registry code 00000) - Data sheets: [TCDS G47EU](https://openairdocs.org/tcds/G47EU) (Alexander Schleicher GmbH & Co. Segelflugzeugbau) (OpenAirDocs) - Serial number: 21930 - Year built: 2015 - Type: Glider - Engine type: None - Airworthiness: Standard, normal - Airworthiness date: September 1, 2015 - Certificate issued: July 2, 2024 - Expires: July 31, 2031 - Mode S code: A9A8BD - Registered owner: [Greater Boston Soaring Club Inc](https://openairdocs.org/faa-owner/GREATER%20BOSTON%20SOARING%20CLUB%20INC) - Location: [Sterling, MA](https://openairdocs.org/faa-place/MA/Sterling) - Owner type: Corporation - Owner's area on the map: 42.4479° N, 71.7760° W: Placed by OpenAirDocs at the center of ZIP code 01564, within about 3 miles (OpenAirDocs). The owner's mailing address, not where the aircraft is based - FAA registry: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=721RC - Page: https://openairdocs.org/aircraft/N721RC From the FAA registry file of October 24, 2026. ADs below are matched by the registry's airframe and engine model codes. They may apply; each AD's applicability can narrow it by serial number, part number or installed equipment. This is not a compliance determination. ## ADs that may apply (OpenAirDocs): 13 in force ### Matched by airframe (Alexander Schleicher ASK 21) - [AD 2017-02-11](https://openairdocs.org/ad/2017-02-11): Flight Controls · Alexander Schleicher ASK 21. Effective Mar 17, 2017 - [AD 2014-06-07](https://openairdocs.org/ad/2014-06-07): Placards and Markings · Alexander Schleicher ASK 21. Effective May 8, 2014 - [AD 95-11-15 R1](https://openairdocs.org/ad/95-11-15-R1): Parallel Rocker · Alexander Schleicher ASK 21. Effective Jul 25, 1999 - [AD 98-12-03](https://openairdocs.org/ad/98-12-03): Rudder Panel, Airbrake Bellcrank, Rear Canopy Hinge · Alexander Schleicher ASK 21, ASW-19 and ASW-19B. Effective Jul 14, 1998 - [AD 98-10-07](https://openairdocs.org/ad/98-10-07): SFM - Weight and Balance · Alexander Schleicher ASK 21. Effective Jun 26, 1998 - [AD 98-09-13](https://openairdocs.org/ad/98-09-13): S-Shaped Rudder Pedal Tube Inspection · Alexander Schleicher ASK 21. Effective Jun 14, 1998 - [AD 98-08-29](https://openairdocs.org/ad/98-08-29): SFM - Stall and Spin Recovery Information · Alexander Schleicher ASK 21. Effective May 18, 1998 - [AD 98-06-38](https://openairdocs.org/ad/98-06-38): Elevator Pushrod · Alexander Schleicher ASK 21. Effective Apr 28, 1998 - [AD 98-06-37](https://openairdocs.org/ad/98-06-37): Tow Release Cable Assembly · Alexander Schleicher ASK 21. Effective Apr 28, 1998 - [AD 97-08-06 R1](https://openairdocs.org/ad/97-08-06-R1): Quick Connectors · Alexander Schleicher AS-K 13, AS 12, ASK 21 and 39 more. Effective Aug 1, 1997 - [AD 87-10-07](https://openairdocs.org/ad/87-10-07): Rudder Pedal · Alexander Schleicher ASK 21. Effective May 13, 1987 - [AD 85-06-07](https://openairdocs.org/ad/85-06-07): Main Wheel Box · Alexander Schleicher ASK 21. Effective Jul 25, 1985 - [AD 84-23-03](https://openairdocs.org/ad/84-23-03): Placard And Afm Changes · Alexander Schleicher ASK 21. Effective Nov 14, 1984 ### Matched by engine (NONE) None in force. ## Information bulletins (advisory) None matched. ## NTSB investigations None matched to N721RC. ## FAA accident and incident reports None matched to N721RC. ## Reports on N721RC not matched to an aircraft (3) They name N721RC, but no registry record covers the date, the aircraft registered then was built later, or the report describes another aircraft. - [Incident 19870706044669I](https://openairdocs.org/incident/19870706044669I), Jul 6, 1987: Boeing 7272S7 (N721RC), Memphis, TN. A system hydraulics failed on climbout. Returned. Found a cracked line. - [Incident 19840103002709I](https://openairdocs.org/incident/19840103002709I), Jan 3, 1984: Boeing 7272S7 (N721RC), Minneapolis, MN, Minor damage. Hit by a parked aircraft that was pushed into the aircraft by a jet blast from a DC-10 taxing from gate. - [Incident 19811219086969I](https://openairdocs.org/incident/19811219086969I), Dec 19, 1981: Boeing 7272S7 (N721RC), Chicago, IL. After takeoff NR3 leading edge flap would not retract. Diverted to Ohare. NR3 leading edge switch bad, replaced. ## Service difficulty reports None filed for this aircraft. Matched to this aircraft by N-number and event date, checked against the reported serial number, make and model. ## Service difficulty reports on N721RC not matched to an aircraft (22) They name N721RC, but no registry record covers the date, the aircraft registered then was built later, or the report describes another aircraft. - [SDR 9904322717](https://openairdocs.org/sdr/9904322717), Sep 20, 1999: FLOORBEAM. DAMAGED. DURING M-CHECK, FOUND MECHANICAL DAMAGE ON UPPER INBOARD FLANGE OF THE LONGITUDINAL FLOORBEAM FS 767, WL 208, LBL 45.5. REPAIRED PER EA 27-170698. - [SDR 9904292717](https://openairdocs.org/sdr/9904292717), Sep 17, 1999: FRAME. CRACKED. DURING M-CHECK, FOUND CRACK ON FRAME INNER CHORD AT FS 950, STR 24L. REPAIRED PER EA 27-120691A. - [SDR 9904302717](https://openairdocs.org/sdr/9904302717), Sep 15, 1999: KEEL BEAM. CORRODED. DURING M-CHECK, FOUND CORROSION ON THE OUTBOARD FLANGE OF THE LEFT KEEL BEAM AT FS 950A+2, WL 148, STR 29L. REPAIRED PER EA 27-168000. - [SDR 9904312717](https://openairdocs.org/sdr/9904312717), Aug 30, 1999: KEEL BEAM. CORRODED. DURING M-CHECK, FOUND CORROSION ON KEEL BEAM LOWER OUTBOARD FLANGE FS 950B+4, WL 148, LBL 8, STR 29L. REPAIRED PER EA 27-168001. - [SDR 9803652717](https://openairdocs.org/sdr/9803652717), Mar 3, 1998: MAG PLUG. DAMAGED. DURING CLIMB AT 10,000 FEET, THE NR 3 ENGINE OIL PRESSURE AND OIL QUANTITY INDICAITONS DROPPED TO ZERO WITH ASSOCIATED LOW OIL PRESSURE LIGHT ILLUMINATION. CREW - [SDR 9714622717](https://openairdocs.org/sdr/9714622717), Jul 24, 1997: CONTROLLER. FAILED. DURING CRUISE FLIGHT, UNABLE TO MAINTAIN CABIN PRESSURIZATION. AIRCRAFT DIVERTED TO ORD AND LANDED WITHOUT INCIDENT. REPLACED CABIN PRESSURE CONTROLLER. OPERATI - [SDR 9704682717](https://openairdocs.org/sdr/9704682717), Mar 2, 1997: PRESSURIZATION. MALFUNCTIONED. DURING CRUISE AT FL350, BEGAN LOOSING CABIN PRESSURE WITH BOTH PACKS IN THE AUTO POSITION. BOTH PACK MIX VALVES WENT TO FULL COLD, THE CABIN PRESSURE BEGAN CLIM - [SDR 9702672717](https://openairdocs.org/sdr/9702672717), Feb 8, 1997: LIGHT. INOPERATIVE. DURING PREFLIGHT, FOUND COCKPIT EMERGENCY EXIT LIGHT INOPERATIVE. REPLACED LIGHT ASSEMBLY, OPERATIONAL CHECK OK. - [SDR 9702092717R](https://openairdocs.org/sdr/9702092717R), Jan 29, 1997: EPR INDICATOR. MALFUNCTIONED. AS TAKEOFF POWER WAS APPLIED, THE NR 3 ENGINE EPR INDICATION DID NOT RESPOND. SYSTEM WAS PLACED ON MEL AND FLIGHT CONTINUED TO DESTINATION. MAINTENANCE LATER RE - [SDR 9701222717](https://openairdocs.org/sdr/9701222717), Jan 12, 1997: RECEIVER. MALFUNCTIONED. DURING CRUISE, THE NR 1 ADF NEEDLE STAYED AT THE 3 O'CLOCK POSITION AND WOULD NOT TEST. AIRCRAFT DIVERTED TO TPA AND LANDED WITHOUT INCIDENT. REPLACED NR 1 ADF - [SDR 9627272717](https://openairdocs.org/sdr/9627272717), Dec 17, 1996: FRAME. CRACKED. DURING 'H' CHECK, THE BS 950E FRAME INNER CHORD AT STR 24L WAS FOUND CRACKED. DAMAGED AREA CUTOUT AND REPAIR INSTALLED PER EA 27-120691. - [SDR 9626522717](https://openairdocs.org/sdr/9626522717), Dec 4, 1996: CHORD. CORRODED. AFT CARGO DOOR LOWER FRAME LOWER 'T' CHORD STR 27R OUTBOARD FLANGE IS EXFOLIATED AT BS 950E TO 970. REPAIRED (P/N 65-56129-10) PER EA 27-120674. - [SDR 9625082717](https://openairdocs.org/sdr/9625082717), Nov 20, 1996: BATTERY PACK. DISCHARGED. DURING PREFLIGHT, FOUND AFT OVERWING EMERGENCY EXIT LIGHT INOPERATIVE. REPLACED BATTERY PACK, OPERATIONAL CHECK OK. - [SDR 9603472717](https://openairdocs.org/sdr/9603472717), Feb 11, 1996: BATTERY PACK. DISCHARGED. DURING PREFLIGHT, FOUND EMERGENCY FLOOR LIGHTS INOPERATIVE IN AFT OF AIRCRAFT. REPLACED BATTERY PACK AND CHECKED OK. - [SDR 9519672717](https://openairdocs.org/sdr/9519672717), Dec 7, 1995: BATTERY. DISCHARGED. DURING PRE-FLIGHT, FOUND EMERGENCY LIGHTS IN VENTRAL STAIRWAY INOPERATIVE. REPLACED VENTRAL STAIRS EMERGENCY LIGHT BATTERIES. CHECKED OK. - [SDR 9511392717](https://openairdocs.org/sdr/9511392717), Jul 26, 1995: HYD PUMP. FAILED. AT FL 300, COMPLETE LOSS OF B-SYSTEM HYDRAULIC FLUID AND PRESSURE OCCURRED. A-SYSTEM HYDRAULIC FLUID DECREASED TO 2.2 GALLONS. DECLARED AN EMERGENCY AND DIVERTE - [SDR 9511132717](https://openairdocs.org/sdr/9511132717), Jul 21, 1995: COMPRESSOR. STALLED. COMPRESSOR STALLS OCURRED IN THE NR 2 ENGINE ON TAKEOFF, THE TAKEOFF WAS ABORTED. THE AIRCRAFT RETURNED TO THE GATE. THE CREW NOTED A DIRECT CROSSWIND FROM THE - [SDR 9511102717](https://openairdocs.org/sdr/9511102717), Jul 19, 1995: SHUTOFF VALVE. FAILED. AFTER TAKEOFF AT FL 070, COULD NOT REINSTATE AIR CONDITIONING PACK. AIRCRAFT WOULD NOT MAINTAIN PRESSURE WITH ONE PACK OPERATION. JETTISONED 8000 POUNDS OF FUEL - [SDR 9509662717](https://openairdocs.org/sdr/9509662717), Jun 12, 1995: EPR TRANSMITTER. MALFUNCTIONED. ON TAKEOFF, THE NR 3 ENGINE EPR INDICATION WAS UNSTABLE AND EXCEEDED THE TARGET VALUE OF THE DAY. THE TAKEOFF WAS ABORTED AND THE AIRCRAFT RETURNED TO GATE. THE - [SDR 9509872717](https://openairdocs.org/sdr/9509872717), Jun 7, 1995: RIB. CRACKED. DURING PERIODIC CHECK, FOUND CRACKS IN THE WING TO BODY UPPER RIB CHORD, BS 760, UPPER FORWARD FASTENER BORE AT LBL 70.5 AND THE LOWER FORWARD FASTENER BORE AT - [SDR 9508052717](https://openairdocs.org/sdr/9508052717), May 16, 1995: RADAR TR UNIT. FAILED. EN ROUTE TO MSP, WEATHER RADAR STABILIZATION FAILED. DIVERTED TO DTW DUE TO THUNDERSTORMS. MAINTENANCE REPLACED RADAR CONTROL PANEL AND TRANSCEIVER. OPERATIONAL - [SDR 9501232717](https://openairdocs.org/sdr/9501232717), Jan 23, 1995: THREADS. DAMAGED. IN CRUISE FLIGHT, NR 2 ENGINE OIL QUANTITY STARTED RAPIDLY DECREASING. A PRECAUTIONARY SHUTDOWN OF THE NR 2 ENGINE WAS PERFORMED A .8 GALLONS INDICATED OIL QUAN ## STCs that may be installed (OpenAirDocs) None matched to this aircraft's models. ## Related - Other Alexander Schleicher ASK 21 aircraft: https://openairdocs.org/model/alexander-schleicher-ask-21/aircraft.md - The NONE engine: https://openairdocs.org/engine/none.md --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.