×
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

Advice on STC for Newbe

Advice on STC for Newbe

Advice on STC for Newbe

(OP)
Hi, hope this is ok to ask here., I am trading my Cessna 170 for a C 180B
The question is, it's O_470J has been replaced by a IO-470L. The 470L has been derated to the same power as the J model 2600 RPM to 2450 RPM. Why?. I can see a cheeper STC complince but can anyone maybe have another reaon? The prop can take the higher RPM. About 30HP increase.
Thanks for any input..

RE: Advice on STC for Newbe

(OP)
Can't edit a post ????
i was asking this more twords a airfram question ranter then a engin question. I am sure there is no engin limitations.

RE: Advice on STC for Newbe

I am guessing here, but could this be related to propeller torque effect?

Usually the propeller is turning clockwise, as viewed from the pilot. This imparts a tendency for the aircraft to rotate counterclockwise (i.e. left wing downwards). This rotation must be counteracted by moving the ailerons. Maybe there is an aileron trim limitation, and incresing this limitation would require an additional mod (more cost) to the ailerons?

RE: Advice on STC for Newbe

(OP)
Thanks, there is something I did not think about -torque- other then engine mounts. But book says only a few mins at full power.

RE: Advice on STC for Newbe

Might also have to do with the requirements of CAR 3.112(a)(2)Longitudinal trim under the following conditions (i) During climb with maximum continuous power at speeds between Vx and 1.4 Vs1

RE: Advice on STC for Newbe

(OP)
Help me understand that CAR. The 180B has no Longitudinal trim. And it does require a lot of right rudder on takeoff which will affect the Longitudinal axes.
Maybe at full throttle with the 30 more HP in a stall could result in a spin easer.
I'm just guessing and wondering why not allow the 30 * hp and use it for very short fields only if needed. In AK so a lot of off airport work or fun.
Thanks for the info..

RE: Advice on STC for Newbe

(OP)
The AC is sold so I guess this does not matter anymore. Should have been faster...

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