Mr. Thomas,

Thank you for the official FAA position on the applicability. Mentioning that there are 2 

different styles of pulleys in the AD and/or service bulletin would help clear things up in my 

opinion. Thanks again for your time

Andy Evans

On Thu, Dec 10, 2015 at 11:55 AM, <Richard.R.Thomas@faa.gov> wrote:

Mr. Evans –

You are not reading it wrong and I appreciate that you want to be sure there is no applicability. That 

said, we have not published AD 2015-24-51 in the Federal Register yet and we are looking at ways to 

make the applicability more clear before we do. Meanwhile you my take my email below as an official 

FAA position relative to the applicability of the AD to the Mott Farm EC120B s/n 1028.

For further confirmation that this is not applicable see the applicability in the attached Air Comm Service 

Bulletin which was issued prior to the AD and is referenced in the AD. Please let me know if this does 

not further confirm no applicability to the Mott Farm aircraft.

Again, my apologies for the confusion.

Respectfully,

Richard R. Thomas

Aerospace Engineer (Mechanical Systems)

ANM-100D Denver ACO

Office - 303.342.1085

Cell - 720.961.3663
From: Andy Andy [mailto:andy@bluesunair.com] 

Sent: Thursday, December 10, 2015 6:56 AM

To: Thomas, Richard R (FAA)

Cc: Bryant, Matthew 

(FAA); Courtney.Liedler@ntsb.gov; emanuele.figlia@airbus.com; KPharris@aircommcorp.com; Trainor, 

Eugene (FAA)

Subject: Re: FW: Mott Farms Response N120RF s/n 1028 - No Damage Reported

Mr. Thomas,

Maybe I am reading this wrong, but in the opening paragraph of this AD states,

This Emergency Airworthiness Directive (Emergency AD) 2015-24-51 is being sent to owners 

and operators of Airbus Helicopters Model EC120B helicopters. This Emergency AD applies 

only to those helicopters that have an Air Comm Corporation (Air Comm) air conditioning kit 

installed in accordance with Supplemental Type Certificate No. SR00491DE.

The STC number Mott Farms Air Comm system is installed under the same number. How does 

one determine if it applies or not? What would be the correct logbook entry to indicate to anyone 

in the future that this AD does not apply?

Thanks Again,

Andy Evans

On Wed, Dec 9, 2015 at 4:50 PM, <Richard.R.Thomas@faa.gov> wrote:

Mr. Evans –

AD 2015-24-51 is not applicable to the original STC SR00491DE configuration installed on the Mott Farm 

EC120B s/n 1028. I must apologize that we did not make this clear on the AD resulting in unnecessary 

inspections on some aircraft including this one. We do appreciate your diligence with respect to the 

AD. Your inspection (particularly the pictures) provides us with some insight into how the original 

configuration is holding up compared to the problem installation which presumably uses the same 

material pulley on the same material spline.
Again, my apologies. You need not take any further action relative to AD AD 2015-24-51.

Respectfully,

Richard R. Thomas

Aerospace Engineer (Mechanical Systems)

ANM-100D Denver ACO

Office - 303.342.1085

Cell - 720.961.3663

From: Andy Andy [mailto:andy@bluesunair.com] 

Sent: Wednesday, December 09, 2015 2:27 PM

To: Thomas, Richard R (FAA)

Cc: Bryant, Matthew 

(FAA); Courtney.Liedler@ntsb.gov; emanuele.figlia@airbus.com; KPharris@aircommcorp.com

Subject: Re: Mott Farms Response N120RF s/n 1028 - No Damage Reported

This pulley sits on the other side of the brake disc. 

On Wed, Dec 9, 2015 at 4:16 PM, <Richard.R.Thomas@faa.gov> wrote:

Mr. Evans –

The picture you provided of the air conditioner pulley looks different than those we’ve seen so far (see 

pictures below). Could you please send a picture of your installation?

Respectfully,
Richard R. Thomas

Aerospace Engineer (Mechanical Systems)

ANM-100D Denver ACO

Office - 303.342.1085

Cell - 720.961.3663
This image cannot currently be displayed.

From: Andy Andy [mailto:andy@bluesunair.com] 

Sent: Wednesday, December 09, 2015 1:03 PM

To: Thomas, Richard R (FAA)

Cc: Bryant, Matthew 

(FAA); Courtney.Liedler@ntsb.gov; emanuele.figlia@airbus.com; KPharris@aircommcorp.com

Subject: Re: Mott Farms Response N120RF s/n 1028 - No Damage Reported

Hello Mr. Thomas,
I did take pictures for our records this time around.(see attached) The owner is asking if there 

will be a different pulley available in the future eliminates this AD? If so any information would 

be greatly appreciated.

Thanks again, any questions feel free to contact me

Andy Evans

On Wed, Dec 9, 2015 at 2:11 PM, <Richard.R.Thomas@faa.gov> wrote:

Dear Mr. Evans –

Thanks for your response. I will add this information to our log and save this to our records as your 

official response to the AD.

I would appreciate it if you could send pictures of both the female and male splines when you 

disassemble and re-inspect in 25 hours as required by the AD. This would help our root cause

investigation.

Respectfully,

Richard R. Thomas

Aerospace Engineer (Mechanical Systems)

ANM-100D Denver ACO

Office - 303.342.1085

Cell - 720.961.3663
From: Andy Andy [mailto:andy@bluesunair.com] 

Sent: Tuesday, December 08, 2015 7:21 AM

To: Thomas, Richard R (FAA)

Subject: AD 2015-24-51 N120RF s/n 1028

To Whom It May Concern,

The following is the requested information from AD 2015-24-51

1- No damage noted on splined joint, Pulley and shaft in good condition

2-Flight hours 515.5 since install

3-A/C S/N 1028

4-No serial number or part number etched on pulley. (this pulley looks different from pulley in 

the pictures from service bulletin SB-EC120-111815)

5-Output Pinion serial number-M32

6-Primary operating location- SW Michigan

7-Approximate usage- 5%

8-Operator and Maintenance- Mott Farms/ Phil Mott-269-649-0458(owner/opr)

Blue Sun Air - Andy@bluesunair.com 616-772-5970

9-No parts replaced, Fully operable

Any more Questions please contact me by email Andy@bluesunair.com or phone 616-648-0747

Thank you

Andy Evans