Ramblings & Comments to Scott's NAMCpedia

I’ve gotten way behind in my comments/additions to Scott’s postings.  He has posted a lot of great tips and references.  Scott is definitely turning this website into the go to site for park jets.  Keep up the good work Scott!  So rather than going back and adding comments, I going to compile them in this posting.

Launch/takeoff- Ailerons Off

Ouch, I’ve crashed several planes at launch.  Practice with something that weighs similar to your plane.  I hold the fuselage at the CG and throw it at 30-degree angle with 45-50% throttle.  Amount of effort is to toss the similar weighing object about 15 feet.

Something that I do differently than Scott is I turns ailerons off.  I program my radio so I can turn the ailerons off with the dual rate switch (not effect the elevons).  

There are several advantages to having an aileron off mix.  These planes fly very well with elevons only.  They fly even better with a touch of aileron input.  Too much aileron and you can turn your plane into a lawn dart—been there, done that.  Same with dual rates, you get fumbled fingered and leave it in high rate at landing—lawn dart.  Yep, did that too.  So when do I turn my ailerons off?  I turn them off at take off to help prevent wing tip stalls.  I also turn them off when I am doing a max throttle high speed fly by.

Spoilers/Flaps

I really enjoy these mixes on the park jets.  Spoilers give you extra degrees of high alpha and flaps are great if you are running a heavy setup like the NTM 2700 prop drive.  When I launch and land a plane with NTM, I always use flaps.  Noticed I used the words spoilers and flaps rather than spoilerons and flaperons.  I turn off the aileron input when I deploy flaps and spoilers.  I have found the plane to be much more stable at slow speeds by not having aileron input to the spoilers and flaps, i.e. spoilerons and flaperons.  The more you upset the airflow over the wings at slow spead, the greater the chance of a wing tip stall.

Performance & Flight Evaluation

Dialing in the ailerons.  I first set up the elevons to get the amount of pitch I want.  Once I am happy with the throws, I then start on the ailerons.  I roll the plane nose up at 50% throttle and dial in the aileron throw to get the desired roll rate.  I am not the rifled bullet make your dizzy type, I like a roll rate that is a little faster than scale (see this in my videos).  

The other maneuvers I like to test are rudder stall turns and knife edge turns.  Of all the maneuvers, the knife edge has been to toughest and what led to the development of the vertical rudder.  I can do a knife edge circle but have yet to do a straight down the runway knife edge.

Whoosh or Stealth

Great observation Scott.  All of my planes make different levels and types of sounds.  As you mentioned, noise is a result of air disturbance and inefficiency.  Taking the time to smooth leading and trailing edges makes a huge difference.  A plane cuts through the air like a knife, which do you prefer sharp or dull?

Push Rods

I’ve tried multiple variations and I agree completely with Scott on the Dubros.  They are way too heavy and a complete pain in the butt to adjust.  I use carbon rods/tubes but a slightly different technique.  For elevon pushrods I use 2mm carbon rods.  Instead of a clevis, I make use wire with a Z bend and piece shrink wrap.  For my NTM planes, I use a 3mm tube that Dubro rods fit nicely inside of.  I will make a how I do it video that will include outboard servo setup that Scott and I use.

Alene’s Tacky Glue

I love this stuff!  It is dirt cheap and I use it for glassing.  FoamTac is great stuff, but way too expensive to use for glassing—if you glass as much as I do.  

I’ve been crazy busy and haven’t had much time for building or flying.  My NAMC v4 only needs servos, rods and KFs.  Hopefully I will get it done this weekend.  Meanwhile, Scott is going to have to build another one because he fatigued the airframe from flying so much!

If Scott’s proposed NAMC’ed Su35 with fixed elevator/elevon flies like I think it will, I know what I’m building next.  Have to keep that one a secret from FRC!

Blue skies to ya!

Stephan