×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

General Aviation Cockpit Instrument Cutout Standards

General Aviation Cockpit Instrument Cutout Standards

General Aviation Cockpit Instrument Cutout Standards

(OP)
Does anyone know if there is a specification or standard that defines typical instrument cutouts and fastener patterns for an aircraft like a Cessna 172?

RE: General Aviation Cockpit Instrument Cutout Standards

?

cut-outs are defined by the instruments.

lay-outs (of the instruments) is something different, if that's what you're after.

RE: General Aviation Cockpit Instrument Cutout Standards

(OP)
In the commercial transport world most instruments are built to ARINC specs to fit in standard rails, standard tray sizes etc. Many systems have standard electrical connector types and even pin assignment layouts.

Standards enables cometition among avionics manufacturers and that competion helps keep prices down for operators.

I don't expect things to be as well defined in GA, but I'm certain every instrument OEM wants you to retrofit to their product as easily as possible.

Airframe builders usually want to drill one set of holes that works for most reasonable customer choices too.

RE: General Aviation Cockpit Instrument Cutout Standards

Not COMPLETELY different in the GA world (I have a foot in both GA and Commercial).  Depending on the instrument, there are standard sizes, but the hole patterns may be very different.  Most instruments have 4 evenly spaced fastener holes (at 1:30, 4:30, 7:30 and 10:30), but some attach from the back of the panel and some from the front.

The panels are analyzed or tested for your particular instruments and panel configuration.

It isn't as tightly controlled presumably because the consequences of a GA aircraft having issues doesn't impact quite as many people.

RE: General Aviation Cockpit Instrument Cutout Standards

Gee guys, this shoulda been a no-brainer:

MS28055, FLANGES, MOUNTING, ATTACHABLE, AIRCRAFT INSTRUMENT

and

MIL-F-6836, "Flanges, Mounting, Attachable, Aircraft Instrument"

From the MIL specs, you can also find the relavant instrument case bodies, fasteners, materials, etc, in addition to the dimensions.
 

Steven Fahey, CET

RE: General Aviation Cockpit Instrument Cutout Standards

(OP)
All,

Thanks for the info.

RE: General Aviation Cockpit Instrument Cutout Standards

Aircraft Spruce also sells the tooling to die cut the openings.  The one thing to be watchful of is that gyros are mounted with slotted fasteners holes to allow alignment with vertical, and some have adjustment knobs that require relief.

RE: General Aviation Cockpit Instrument Cutout Standards

We do custom panels on a waterjet.  The issue is visibility of the instrument panel / PFD.  If I cut a hole to fit the altimeter, but I can't see it through the yoke, it won't "fly".  There are installation requirements, but those are pretty simple to meet.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources