News:


Advertise Here

  • May 23, 2022, 08:19:05 AM

Login with username, password and session length

Author Topic: ARF SV11 incidence check.  (Read 474 times)

Offline Manuel Cortes

  • Trade Count: (0)
  • Commander
  • ****
  • Posts: 272
ARF SV11 incidence check.
« on: January 29, 2022, 04:45:46 AM »
Hi all.
I am in the assembling process of a Brodak ARF SV11. Before epoxy mix I have check the engine-wing-stab incidence and have discovered that he engine trust line performs a -1,6║ (negative, downtrust incidence).
It is obvious than every Brodak ARF-ARC SV11 reviewed here performed very well, so I suspect a eventual unit defect, but I want to know if any of you had checked the incidence and your results.
By the way, I will shim the alu pads for a 0-0 trustline adjust before assembling the model.

Thanks for your time and kind regards from Spain.

Manuel.

P.S. The weight is excellent, expecting 58-60 oz with a T&L ST60.

Online Dan McEntee

  • 2015
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 5551
Re: ARF SV11 incidence check.
« Reply #1 on: January 29, 2022, 07:02:29 AM »
      I would not change that down thrust. If you are a PAMPA member, go through the back issues for an article by Bob Whitely titled "Things That Always Work" and in that article he points out always building in about 1 degree of down thrust, 1 degree of right thrust, and 1 degree of positive incidence in the horizontal stab. These are all to offset forces form the prop and engine and every model I have flown since reading that article has been set up that way. With the ST.60 and the pitch that is usually used with that engine, I think that you will want these adjustments and like them. With these setting and other basic bench trimming techniques I usually get a model that tracks well enough to fly the pattern from the first flights.
  Type at you later,
  Dan McEntee
AMA 28784
EAA  1038824
AMA 480405 (American Motorcyclist Association)

Offline John A Miller

  • Trade Count: (0)
  • Ensign
  • **
  • Posts: 40
Re: ARF SV11 incidence check.
« Reply #2 on: January 29, 2022, 12:27:36 PM »
I most totally agree with Dan. Leave the engine engine down thrust alone. My results using Bob Whitley's suggestions from his article, "Things that always work', have mirrored Dan's results.
The numbers I use are, 1 -2  degrees down thrust (for a counter clockwise turning prop). Just enough out thrust so you are sure there is no in thrust, and Positive stab  incidence. According to Dave Fitzgerald's writings on the subject,, this positive incidence can be achieved by raising the stab leading edge by placing a narrow strip of 1/64" plywood under the stab leading edge.

Good Luck and HAPPY FLIGHTS
John Miller

Offline Manuel Cortes

  • Trade Count: (0)
  • Commander
  • ****
  • Posts: 272
Re: ARF SV11 incidence check.
« Reply #3 on: January 29, 2022, 02:29:32 PM »
Thanks very much for your words, guys, deeply appreciated.

Kind regards from Spain.

Manuel.

Kind Regards.

Manuel CortÚs.


Offline Doug Moisuk

  • 22 supporter
  • Trade Count: (0)
  • Commander
  • *
  • Posts: 194
Re: ARF SV11 incidence check.
« Reply #4 on: February 04, 2022, 11:22:34 AM »
I would check with the designer Randy Smith. He also had a lot to do with the production of the kits.
Doug Moisuk
MAAC 3360L

Online Ken Culbertson

  • 22 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 4477
Re: ARF SV11 incidence check.
« Reply #5 on: February 04, 2022, 01:32:55 PM »
"Things that always work"
I have been unsuccessful in finding the article so I will ask.  Are we talking using all three bench adjustments?  Down thrust, right thrust and stab incidence?

Anyone know about when that article was?

Ken
« Last Edit: February 05, 2022, 12:22:39 AM by Ken Culbertson »
AMA 15382
If it is not broke, don't fix it.
USAF 1968-1974 TAC

Online Dan McEntee

  • 2015
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 5551
Re: ARF SV11 incidence check.
« Reply #6 on: February 04, 2022, 01:51:59 PM »
I have been unsuccessful in finding the article so I will ask.  Are we talking using all three bench adjustments?  Down thrust, right thrust and stab incidence?  What this amounts to is mounting the stab parallel to the thrust line.  Would not mounting the wing with 1 degree positive do the same thing?   I ask this because I have a fuselage on the table now that does not have any downthrust and it cannot be added, BUT, the wing is not in yet so..........

Anyone know about when that article was?

Ken

    https://stunthanger.com/smf/stunt-design/changing-stab-height/msg630902/#msg630902

    It was brought up on the recent stab location thread.   Stunt News July/August 1998.  I don't know of anyone that has approached it the way you are thinking.  I can't imagine a power plant that I can't adjust some how. I always use 3 incidence meters, one on the wing, one on the engine and one on the stab to set up a model. For the one on the stab I usually pull the mounting bar out of the gauge portion and just set it on the stab if it's a smallish model.  If you can't come up with the article, message me an email address or a mobile phone number and I can take a picture of it and send it to you.
  Type at you later,
   Dan McEntee
AMA 28784
EAA  1038824
AMA 480405 (American Motorcyclist Association)


Advertise Here
Tags:
 


Advertise Here