Doug Poli, Technical Representative for the SX300 Group, has 20 years of SX experience. His continuing efforts with modifications and improvements to the kit have made the SX 300 a better and safer aircraft. This page is devoted to his ongoing upgrades, modifications, information, available parts and other features to enhance the safety and performance of  the SX 300.

Doug at work

Doug at play


Doug Poli can be reached at 817 988-0859 or e-mail This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Click On Any Link Below To See More Details


Doug's Hangar List of available Hydraulic Actuator and Shock Strut Seals.


Doug's Hangar List of available SX 300 parts for sale. Oil Filter Drain Kit. (see drawing).


Doug's Hangar Trunnion Failure. Doug Poli has a source for new improved landing gear trunnions.

See photos of new design trunnion versus original trunnion.


Hangar News Power Pak Pressure Switch Upgrade. Airight, Inc. is offering a new pressure switch for use on their Power Paks. The switch PN 91450-1 is more reliable than previous switches, so be sure to specify this PN when ordering. See drawing  for switch location on Power Pak.


Hangar News NLG Rigging And Inspection. The Nose Landing Gear Retraction System parts are showing wear on SX's with 300 or more hours in service. Refer to drawing for specific inspection items.


Hangar News Engine Air Box Sides Modification. Inspection of engine Air Box sides on aircraft with 200 or more hours has revealed cracking and elongated attach screw holes. See Doug's write up and detailed drawing.


Cooling Baffles Cylinders # 3 and  # 4 have a tendency to run hotter than the other cylinders. Click on this link to see photo and sketch of  Cooling Baffles that will correct this problem.


Doug's Hangar NLG Wheel Axle Plug Recess. The RH  NLG Wheel Axle Plug sits on the outside of the fork creating a close fit between the plug and the NLG  Drag Brace weldment when wheel is retracted. See photo and Doug's idea to prevent this from happening.


Fresh Air System Additional Fresh Air System. This system takes air from the engine cooling air box and directs it into the cockpit. See photo and read more information about this system.


Fresh Air System NACA Duct (Scoop). See photo of an easy way to improve the fresh air ventilation system in your SX.


Oil Cooler Oil Cooler Air Flow Modification. Photos and drawing show how to increase air flow to oil cooler for lower oil temperature(12 to 15 deg.) and how to improve heater efficiency.


Hangar News SX 300 Hydraulic System Schematic.


Hangar Talk Electric Aileron Trim System. A worthwhile modification for the aileron trim system is the installation of the Ray Allen Co. Inc. electric servo. This eliminates the existing springs and cable system. More information and a drawing of the installation can be seen on this link.


Hangar Talk Electronic Ignition. ElectroAir offers an electronic ignition unit that really works well and is easily installed. Drawing and photo.


Hangar Talk Power Pak Fluid Recovery Can. This large capacity can ("Burp Can") catches the fluid that would normally go overboard when checking the "Free Fall" Landing Gear Extension system and drains it back into the reservoir. Photo and drawings.



SX300 Home Doug's Page

canakkale vergi mevzuati bagimsiz denetim bagimsiz denetim web security ozurluler bilisim teknoloji sgk bagimsiz denetim bagimsiz denetim sorgulama internet security mevzuat vergi ve sgk mevzuati