EASA AD No.: 2011-0148 

EASA Form 110 Page 1/3

EASA AIRWORTHINESS DIRECTIVE 

AD No.: 2011-0148 

Date: 05 August 2011 

Note: This Airworthiness Directive (AD) is issued by EASA, acting in accordance with 

Regulation (EC) No 216/2008 on behalf of the European Community, its Member States and 

of the European third countries that participate in the activities of EASA under Article 66 of 

that Regulation.

This AD is issued in accordance with EC 1702/2003, Part 21A.3B. In accordance with EC 2042/2003 Annex I, Part M.A.301, the 

continuing airworthiness of an aircraft shall be ensured by accomplishing any applicable ADs. Consequently, no person may operate 

an aircraft to which an AD applies, except in accordance with the requirements of that AD, unless otherwise specified by the Agency 

[EC 2042/2003 Annex I, Part M.A.303] or agreed with the Authority of the State of Registry [EC 216/2008, Article 14(4) exemption]. 

Type Approval Holder’s Name : 

Eurocopter Deutschland GmbH 

Type/Model designation(s) : 

MBB-BK117 helicopters 

TCDS Number : EASA.R.010 

Foreign AD : Not applicable 

Supersedure : This AD supersedes EASA AD 2011-0131 dated 08 July 2011. 

ATA 85 Optional Equipment – External Rescue Hoist System –

Deactivation / Modification 

Manufacturer(s): Eurocopter Deutschland GmbH (ECD), Eurocopter Hubschrauber GmbH, 

Messerschmitt-Bölkow-Blohm GmbH 

Applicability: MBB-BK117 A-1, MBB-BK117 A-3, MBB-BK117 B-1, MBB-BK117 B-2 and 

MBB-BK117 C-1 helicopters, all serial numbers. 

Reason: In a recent incident with a MBB-BK117 C-1 helicopter, the cable cut-off 

function of the rescue hoist was triggered uncommanded and the hoist cable 

was cut. The subsequent investigation revealed that this was caused by a 

malfunction within the remote control handle assembly of the rescue hoist 

system, when extending the hoist boom. 

This condition, if not detected and corrected, would lead to detachment of an 

external load or person from the helicopter hoist, possibly resulting in 

personal injury, or injury to persons on the ground. 

The same Part Number (P/N) 117-80403 and P/N 117-804061 hoist systems 

are known to be installed on other models of the same type design. 

To address this potential unsafe condition, EASA issued AD 2011-0126 to 

require deactivation of the affected external hoist system by pulling and 

securing the related circuit breakers, or by removing the hoist boom. Pending 

the results of the investigation, EASA AD 2011-0126 also prohibited 

installation of an affected external hoist system on any other helicopter. 

Following issuance of EASA AD 2011-0126, it was discovered that by pulling 

the circuit breaker WARN ANN II, the redundant power supply of the 
EASA AD No.: 2011-0148 

EASA Form 110 Page 2/3

Annunciator System is degraded which in case of second helicopter system 

failure could be not annunciated to pilots. Prompted by these findings, EASA 

issued EASA AD 2011-0131, which superseded EASA AD 2011-0126, 

retained partially its requirements and required pulling only three (3) circuit 

breakers (CABLE CUTTER, WINCH CONT. and WINCH BOOM) while the 

circuit breaker for WARN ANN II must remain inserted. 

Since EASA AD 2011-0131 was issued, a corrective action has been 

developed to establish an adequate safety level, while a terminating action is 

under investigation but currently not available. 

For the reasons described above, this AD retains the requirements of EASA 

AD 2011-0131, which is superseded, and requires repetitive inspections of 

the external hoist system control handle with coiled cable, Part Number (P/N) 

76803, modification of helicopter wiring and a revision of the related Flight 

Manual Supplement. This AD also requires implementation of a 10-year time 

between overhaul (TBO) for the external hoist system control handle with 

coiled cable. This AD is still considered to be an interim measure and further 

AD action may follow. 

Effective Date: 12 August 2011 

Required Action(s) 

and Compliance 

Time(s): 

Required as indicated, unless accomplished previously: 

Re-statement of requirements of EASA AD 2011-0131: 

(1) For helicopters equipped with (optional) rescue hoist (sometimes 

referred to as rescue winch), P/N 117-80403 or P/N 117-804061, 

accomplish one of the actions, paragraph (1.1) or (1.2) below: 

(1.1) Before the next hoist operation, or within 30 days, whichever 

occurs first after 12 July 2011 [the effective date of AD 2011-0131], 

deactivate the external hoist system by pulling the three (3) 

affected circuit breakers, CABLE CUTTER, WINCH CONT. and 

WINCH BOOM, and securing each with a cable tie, or 

(1.2) Before the next hoist operation, or within 30 days, whichever 

occurs first after from 05 July 2011 [the effective date of EASA AD 

2011-0126], remove the hoist boom in accordance with the 

instructions of Chapter 832 of the applicable ECD MBB-BK 117 

Maintenance Manual. 

(2) For all other helicopters, from 05 July 2011 [the effective date of EASA 

AD 2011-0126], do not install an affected P/N rescue hoist, as identified 

in paragraph (1) of this AD, on any helicopter, unless the installation is in 

compliance with the requirements of paragraph (1) or in compliance with 

the requirements of paragraph (3) of this AD. 

New requirements of this AD: 

(3) For helicopters equipped with (optional) rescue hoist, P/N 117-80403 or 

P/N 117-804061, before the next hoist operation, or within 30 days, 

whichever occurs first after the effective date of this AD, accomplish the 

following actions concurrently: 

(3.1) Modify the helicopter wiring and the operator handle P/N 76803 to 

deactivate the external hoist system cable cutter function in 

accordance with the instructions of ECD Alert Service Bulletin 

(ASB) MBB-BK117-80-166 Revision 1 (Rev.1), and 

(3.2) Replace the affected pages of the relevant Rotorcraft Flight 

Manual (RFM) and its applicable Supplement (RFMS) with the 

applicable Temporary Revision (TR) as listed in Table 1 of this AD, 

to incorporate pre-flight check instructions for the condition of the 

control handle P/N 76803, including the coiled cable. 
EASA AD No.: 2011-0148 

EASA Form 110 Page 3/3

Table 1 

RFM TR No. 

BK117 C1C 2 

BK117 C1 3 

BK117 B2 S/N7203 2 

BK117 B2 2 

BK117 B1 7 

BK117 A4 6 

BK117 A3 10 

 

(4) Concurrent with the modification as required by paragraph (3) of this 

AD, and thereafter at intervals not to exceed 30 days (+ 10% tolerance), 

inspect the control handle P/N 76803 for damage, in accordance with 

the instructions of ECD ASB MBB-BK117-80-166 Rev.1.

(5) If, during any pre-flight check as required by paragraph (3) of this AD, or 

during any inspection as required by paragraph (4) of this AD, damage 

is detected, before the next hoist operation, replace the control handle 

P/N 76803 with a serviceable part. 

(6) From the effective date of this AD, do not install a control handle P/N 

76803 on any helicopter, unless it has been modified in accordance with 

the instructions of ECD ASB MBB-BK117-80-166 Rev.1.

(7) Modification of a helicopter as required by paragraph (3) of this AD 

cancels the requirements of paragraph (1) of this AD for that helicopter. 

(8) Within 10 years after first installation on a helicopter, or within 9 months 

after the effective date of this AD, whichever occurs later, and thereafter 

at intervals not to exceed 10 years, accomplish an overhaul of the 

control handle P/N 76803. 

Ref. Publications: 

ECD ASB MBB-BK117-80-166 Revision 1 dated 04 August 2011. 

The use of later approved revisions of this document is acceptable for 

compliance with the requirements of this AD. 

Remarks : 1. If requested and appropriately substantiated, EASA can approve 

Alternative Methods of Compliance for this AD. 

2. The required actions and the risk allowance have granted the issuance 

of a Final AD with Request for Comments, postponing the public 

consultation process after publication. 

3. Enquiries regarding this AD should be referred to the Safety Information 

Section, Executive Directorate, EASA. E-mail ADs@easa.europa.eu 

4. For any question concerning the technical content of the requirements in 

this AD, please contact: 

Eurocopter Deutschland GmbH, Industriestrasse 4, 

86607 Donauwörth, Federal Republic of Germany 

Telephone: + 49 (0)151-1422 8976; Facsimile: + 49 (0)906-71 4111.