Seaplanes Aircraft that typically take off and land on water...radio control seaplane discussions are in here.

Thrust angle for sea plane??

Reply
Old 05-09-2010, 08:38 AM
  #1
shawnr1975
Thread Starter
 
Join Date: Mar 2010
Location: Burley, ID
Posts: 5
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default Thrust angle for sea plane??

Can anyone tell me what the thrust angle should be up, down, left or right for a sea plane. The engine pod is mounted in front of the wing so it pulls. Any help would be great! Thanks!!
shawnr1975 is offline  
Reply With Quote
Old 05-09-2010, 10:07 AM
  #2
ryanpilot
 
ryanpilot's Avatar
 
Join Date: Aug 2004
Location: Burley, ID
Posts: 250
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Thrust angle for sea plane??

To expand on Shawn's post a little.... He has a Neptune type plane with the pod mounted engine above the cockpit in a tractor config. Besides the thrust angles does any one have a copy of the ols Seamaster plans and know what the incidence angle for the horiz stab is?
ryanpilot is offline  
Reply With Quote
Old 05-09-2010, 01:01 PM
  #3
MinnFlyer
 
MinnFlyer's Avatar
 
Join Date: Apr 2002
Location: Willmar, MN
Posts: 28,519
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Thrust angle for sea plane??

Thrust should be 1 or 2 degrees up

Stab/wing should be at Zero
MinnFlyer is offline  
Reply With Quote
Old 05-09-2010, 02:25 PM
  #4
JimCasey
 
JimCasey's Avatar
 
Join Date: Mar 2002
Location: Lutz, FL
Posts: 1,957
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Thrust angle for sea plane??

A high-mounted engine like that tends to lever the nose down when you add throttle. Minnflyer says 1-2 degrees, I lean a little harder toward three degrees up. And since the prop is now facing a pretty significant incidence up, the right side of the prop takes a bigger bite and tries to turn the plane left. Add 3 degrees right thrust as well. What ypu DON'T want is for the thrust to force the nose down just when you goose the throttle in an aborted landing.
JimCasey is offline  
Reply With Quote
Old 05-09-2010, 02:33 PM
  #5
shawnr1975
Thread Starter
 
Join Date: Mar 2010
Location: Burley, ID
Posts: 5
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Thrust angle for sea plane??

Thanks Jim, that helps alot!!
shawnr1975 is offline  
Reply With Quote
Old 05-10-2010, 07:32 AM
  #6
Mustang Fever
 
Mustang Fever's Avatar
 
Join Date: Nov 2003
Location: Cadillac, MI
Posts: 3,225
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Thrust angle for sea plane??

I have one of the Lanier Mariner 40s, and they put approximately 4 degrees upthrust in the pod. Experience with it has shown me that 5 degrees would have been better, as it still wants to drop the nose on throttle up from any speed.
Mustang Fever is offline  
Reply With Quote
Old 05-10-2010, 12:32 PM
  #7
Bob93447
 
Join Date: Sep 2004
Location: Playa del Rey, CA
Posts: 288
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Thrust angle for sea plane??

Has anyone done a similiar analysis for the Great Planes Seawind where the pod is attached behind the CG?
Bob93447 is offline  
Reply With Quote
Old 05-10-2010, 12:49 PM
  #8
MinnFlyer
 
MinnFlyer's Avatar
 
Join Date: Apr 2002
Location: Willmar, MN
Posts: 28,519
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Thrust angle for sea plane??

I believe the Seawing has a slight downward angle
MinnFlyer is offline  
Reply With Quote
Old 05-10-2010, 01:50 PM
  #9
Mustang Fever
 
Mustang Fever's Avatar
 
Join Date: Nov 2003
Location: Cadillac, MI
Posts: 3,225
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Thrust angle for sea plane??

It might benefit from more down thrust. Haven't flown one, so don't know for sure. The Mikulasko Arrow is similar, with a very high mounted, aft of the CG engine. I built and destroyed three of them before I put 5 degrees downthrust on number 4, and all the handling problems disappeared.
Mustang Fever is offline  
Reply With Quote
Old 07-03-2010, 11:16 PM
  #10
DwightMann
 
Join Date: Sep 2004
Location: Mohave Valley, AZ
Posts: 168
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Thrust angle for sea plane??

Does anybody have a recommendation for the thrust angles on a grumman widgeon ( twim engine mounted on the wings)?
DwightMann is offline  
Reply With Quote
Old 07-04-2010, 05:47 AM
  #11
Mustang Fever
 
Mustang Fever's Avatar
 
Join Date: Nov 2003
Location: Cadillac, MI
Posts: 3,225
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Thrust angle for sea plane??

All the flying boat models I'm familiar with that have wing mounted engines (on high wing locations) use zero-zero thrust lines. (Catalina, PBM Mariner, CL-215, etc.) Because of this, they all fly nice and straight once airborne. On the water, they all want to bury the bow when you throttle up, but because they all have the horizontal stab in line with the props, a little up elevator counters that tendency and they plane up real nice.
Mustang Fever is offline  
Reply With Quote
Reply


Thread Tools
Search this Thread
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -8. The time now is 12:24 AM.