FB Jets Dolphin S User manual

FB Jets Dolphin
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Written By Rich Miller in Collaboration with Fei Bao Jets
Rev 0

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Contents
DISCLAIMER: 4
Introduction 4
Specifications 6
Component Size (Length) 6
Construction 6
Adhesives 7
Standard Pneumatic LG Systems 7
Optional Electric LG Systems 7
Parts List: 8
Optional Equipment 8
Additional Equipment 8
Optional Equipment (Builders choice) 9
Servo List (Hi-Tec) based on 6V torque specifications 9
Servo List (JR) based on 6V torque specifications 9
Construction 10
Pneumatic Landing gear 11
General 11
Step 1: Nose Gear 11
Step 2: Main Landing Gear 12
Step 3: Forward Fuselage 13
Optional Battery Box 14
Step 4: Fuel Tanks 14
Tank Assembly 16
Tank Mounting 17
Saddle Tanks: 17
Optional Mounting: 18
Main Tank & Auxiliary tank: 19
Optional Mounting: 20
Step 5: Final Fuel System plumbing: 21
Step 6: Air Tank Installation 22
Step 7: Aft Fuselage 22
Step 8: Wing –Servo Installation 23
Figure 1- Wing servo layout 24
Optional wing servo connector Components 25
Figure 2 –Optional servo connector mounting 25
Step 9: Vertical Fin and Rudder servo installation 25
Figure 3 –Hole placement in vertical fin 25

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Figure 4 –Fin and ruder servo layout 26
Step 10: Horizontal Stabilizer and Elevator servo installation 27
Figure 5 –Stabilizer servo layout 28
Front equipment tray 30
Step 12: Turbine Mounting Rails and Tail Pipe 31
Step 13: Turbine Accessory Installation 32
Step 14: Cockpit 33
Step 15: Radio Channel Assignments 34
Step 16: CG 34
Step 17: Setting of throws 34
Maintenance Tips: 35
Annex A 36

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DISCLAIMER:
THIS IS NOT A TOY
This is a high-performance miniature aircraft, capable of high speeds and damage to life, limb, and
property. The manufacturer and its distributors and author of this manual cannot control how you
assemble this model, what equipment you use to fit it out, or how you fly it, and can assume no
liability whatsoever for any damages that may occur when you fly your aircraft. By assembling this
model, you are agreeing to indemnify and hold blameless the manufacturer and/or his agents from
any and all torts and liability associated with the use of this product.
Please inspect all parts before beginning assembly. If any part appears to be suspect, contact your
dealer or the manufacturer for repair or replacement BEFORE you begin.
Once you have assembled the aircraft, you are the pilot in command and assume any and all
responsibility for the use of the model and any damages that might occur by flying or attempting to
fly this aircraft.
R/C model jets require a high level of skill in both their assembly and their flying. If you do not feel
confident in either your building or flying skills, PLEASE seek assistance from more experienced
modelers. It is a wise idea, no matter what level of skills you possess, to have a second
experienced modeler go over your installation after assembly. A second set of eyes may spot a
problem you have missed. If you have not flown a high performance model like this before, it is
HIGHLY recommended that you get an experienced turbine pilot to do your maiden flight. Very
often, the first few seconds of a maiden flight are critical until the aircraft is trimmed out, and having
an experienced pilot at the controls can make the difference between a wrecked aircraft and once
that enjoys many hundreds of flights. Be sure to select a suitable field for flying...take the time to
find a large paved runway if at all possible, especially for test flights, until you feel comfortable
getting the aircraft in and out of smaller grass fields.
Note: In the USA it is mandatory that you belong to the Academy of Model Aeronautics and hold a valid Turbine Waiver, please check
the local governing rules for operation of R/C model jets of your location before flying.
Congratulations on your purchase of the FB Jets Dolphin
Introduction
You have chosen a model that represents the pinnacle of ARF technology and factory testing with
the new manufacturing processes implemented by FB Jets. While there is not a lot of building to
do, there is enough to keep you busy for quite a few evenings. Even if you have assembled other
ARF jets, we highly recommend following the assembly sequence and procedures presented in
this manual.
Please remember that just because the model is almost completely built it does not mean that you
can rush through the final install / assembly. It is this authors recommendation that any factory
installed systems such as hardware, linkages, fuel lines, retracts, wheels and brakes, be inspected
for any possible defects, loose parts etc., and all fasteners should be secured with Loctite. Wheels
and brakes should be checked for lubrication and for proper fit to the axel; threads on linkages
should be inspected for tightness.

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The Dolphin was designed to be modular to make for easy transportation, see “component size” in
the specification section. The forward and aft fuselage sections bolt together with four bolts. The
thrust tube (pipe) remains in the aft section of the fuselage when the halves are separated. When
attaching the front and rear halves of the fuselage, the thrust tube can be slid towards the back to
allow clearance to gain access to the four fuselage mounting bolts. After joining the two halves,
the thrust tube can then be slid forward to allow the mounting tabs of the bell mouth to be screwed
to the motor mount rails.
The Vertical fin is easily removed / installed utilizing the two internal clamping mechanisms that are
easily tightened with hex (Allen) wrenches through the access holes in rear fuselage as shown.
The right horizontal stabs has an integral carbon fiber spar, the left has a built in tube socket. Both
have an anti-rotation pin located towards the leading edge. The right stab is inserted into the
integral tube in the aft section of the fuselage. Upon complete insertion, the spar will protrude
through the fuselage allowing the other stab to be slid onto the spar tube. The stabs are then
attached with one allen bolt into the CF spar, bolt location shown in photo.
The wings utilize a carbon fiber main spar and have two anti-rotation pins towards the front and
rear of the root rib, they attach to the fuselage using a thumb screw that is accessed through the
landing gear wheel well.
When the model is taken apart it will fit in a small area for transportation.

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Specifications
Total Length: 104 1/8” (2645 mm)
Total Wingspan: 91 3/4" (2330 mm)
CG Location 28% MAC: 11 7/16” (291 mm) from LE of Wing
Prototype Dry Weight with all components: 35 lbs (15.9 Kg)
Thrust Class: 30 to 42 lbs (130N to 190N)
Servos for Flight Surfaces & Steering (8)
Servos for pneumatic controls (2) or pneumatic valves
Fuel Capacity Right and Left Saddle Tanks: 37 oz ea (1100 ml ea)
Prototype Supplied Center Tank* 47 oz (1400 ml)
Additional Builder Supplied Tank* 34 oz (1000 ml) for additional capacity
Total Capacity 155 ½ oz (4600 ml)
Main Tire Diameter 4.3” (109 mm)
Nose Tire Diameter 3.25” (82.5 mm)
* Factory to supply larger tank in production model
Component Size (Length)
Vertical Fin –18 ¾” (475 mm)
Horizontal Stab (ea.) –16 3/8” (415 mm)
Wing Panel (ea.) –38 ¼” (971 mm)
Canopy –45” (1143 mm)
Forward Fuselage –70 3/8” (1787 mm)
Aft Fuselage –33 5/8” (854 mm)
Thrust Tube (Pipe) Length: 37” (940 mm)
Pipe Diameter: 3 ½” (89 mm)
Bell Mouth Length: 2.75” (70 mm)
Total Pipe Length with Bell Mouth: 39 ¾” (1010 mm)
Construction
Preliminary Steps before you begin
Keep this in mind as you proceed
Look at EVERY assembly step you finish, and ask yourself:
“Could this cause a malfunction and crash my aircraft?”
A chain is only as strong as its weakest link, and this is a high-performance aircraft that will be
intolerant of sloppy assembly techniques. Even the smallest component is important and can
cause the loss of your airframe, so take the time to do things right, or redo them if they are wrong.
Careful work will result in a long lasting aircraft that will give you years of pleasure, one loose
component could resulting the complete loss of the aircraft and all of the component inside of it,

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additionally someone could even get hurt. So please pause every once in a while when building
and double check your workmanship.
Clean and inspect all parts. Inventory them against the parts list at the end of the manual and
notify the kit supplier of any missing components as soon as possible.
If the paint scheme you have selected is glossy, it is recommended that you apply a coat of
wax. This will help resist dirt, stains and fingerprints during construction, and will provide some
limited protection against errant glue.
Vacuum out the remnants of packing materials that remain in the fuselage.
Adhesives
The author prefers Loctite Hysol 9462 adhesive for all procedures. This is a very strong epoxy that is
thixotropic. “Thixotropic” means it does not run at all, but stays only where you put it. It is superior to
regular epoxy, even slow setting epoxy, because of this characteristic. Regular epoxy will run with
gravity as it dries, taking it away from where it is supposed to be. The downside of Hysol is it takes
overnight to dry properly. It is recommended that you only use a proper Hysol dispensing gun and only
the long-type mixing nozzles.
Be careful if using adhesives such as “shoe goo” or Zap-a-Gap-a-Goo, as these contain solvents that
may attack the fiberglassand could ruin the surface finish of your model.
Standard Pneumatic LG Systems
Pneumatic retracts typically are the number one maintenance issue with most models however with
proper installation procedures and preventive maintenance this need not be the case. The Dolphin
uses pneumatic retract and brakes. If you follow a few tips you should have a very reliable leak free
operation. Factory installed systems should be inspected for kinked lines, proper insertion of hoses on
fittings and the hose routings should be neat and secure. Special attention should be made to ensure
that the length of tubing at “T” fitting is equal to both sides to ensure balance operation, epically in the
brake system. Take special precautions to route hoses away from moving landing gear parts and hot
engine areas. It is recommended that the factory valves, cylinders and brakes be dissembled, cleaned
and lubed with a good O-ring lubricant to ensure reliable operation.
If installing your own pneumatic components it is important to make all cuts in the pneumatic tubing
dead square before installing on the nipples, also make sure that the lines are pushed all of the way
onto the nipples. They should not need to be secured otherwise however you can add fine safety wire
for extra security.
Optional Electric LG Systems
At the time of writing of this manual it was announced that FB Jets will offer optional electric retracts for
this model.

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Parts List:
Major components
Fuselage front Section with nose retract installed
Fuselage aft section
Canopy
Forward and Aft Equipment trays
Right and Left Wing panels with main retracts installed
Right and Left Horizontal Stabilizer
Vertical Stabilizer
Tail Pipe with Bell Mouth
Right and Left Saddle Tanks
Center Tank
Tank Hardware/Heavy Clunks/Aluminum Bung Fittings
Linkages / Hardware kit
Air Kit: Tanks, Lines, Valves
79” (200cm) Blue Air Line
79” (200cm) Red Air Line
79” (200cm) White Air Line
79” (200cm) Yellow Air Line
3 Three port valves (Gear & Doors)
1 One Port Valve (Brakes)
2 Air Tanks
1 Fill Fitting
6 Three port Y’s
4 four port Tees
4 Disconnects
Optional Equipment
Sport Scale Cockpit
Electric Retracts Optional
AdditionalEquipment
While the kit is comprehensive, there are additional parts required as follows:
Turbine –Thrust Class: 30 to 42 lbs (130N to 190N) The Prototype was powered with the
Jet Central Rhino SP
Radio System (Users Preference of Manufacturer)
Servos (See List on next page)
Servo Extensions Various Lengths depending on equipment locations
Servo lead bulkhead connectors (ideal for fuselage junction and wing connections)
Batteries / Regulator / Switch / Power system
Adhesives (Thin CA, Medium CA, Hy-Sol, Loctite Red/Blue)
3/16” Tygon fuel line
3/16”(5 mm) Brass Fuel Line (K&S P/N 1147) 5 mm (K&S P/N 3923)
S.S. Tie wire

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Ty-Raps
Bulkhead fittings
Festo Fuel Valves
Miscellaneous small screws
Sullivan 4-40 Gold-N-Clevises or equivalent
BVM UAT or equivalent (optional / but highly recommend) Users Preference of
Manufacturer
Air Pressure Gauge
Optional Equipment (Builders choice)
(Optional Internal Finishing) Grey Primer and Paint such as RUST-OLEUM Stone Textured
Paint (Grey)
Optional fuel tank Nalgene™ HDPE auxiliary tank Mfg. P/N 2007-0032
Fittings for optional fuel tank
DB-9 Connector Male & Female
Wiring harness
Servo List (Hi-Tec) based on 6V torque specifications
Ailerons: (1) HS-5625MG or HS-7985MG
Elevator: 2) HS-7955TG
Flaps: (2) HS-7955TG
Rudder: (1) HS-7955TG
Nose Steering: (1) HS-645MG or HS-5645MG
Mechanical Retract Valve: (1) HS-225 (MG) or Electronic Pneumatic Dual Action Valve
Mechanical Brake Valve: (1) HS-225 (MG) or Electronic Pneumatic Single Action Valve
Servo List (JR) based on6V torque specifications
Ailerons: (2) DS8411
Elevator: (2) DS8611A or DS8711
Flaps (2) DS8611A or DS8711
Rudder: (1) DS8611A or DS8711
Nose Steering: (1) 4721
Mechanical Retract Valve: (1) 351 or Electronic Pneumatic Dual Action Valve
Mechanical Brake Valve: (1) 351 or Electronic Pneumatic Single Action Valve

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Construction
The order of construction may be changed to suit your personal preference; however, due to the
size of the Dolphin it is recommended to complete as much of the work as possible on the
individual components before the final assembly. The majority of the assembly takes place in the
forward fuselage section. It is recommended installing a servo lead bulkhead connector at the
fuselage junction; this will allow easy disassembly for transportation.
The prototype used for the creation of this manual utilized a standard DB-9 “D-Type” connector
(See photo); however, any connector system could be utilized including standard servo extensions.
Note: If using individual servo extensions, it is a good idea to mark each lead with an identifier to
aid during re-attachment.
Aft Fuselage Front Fuselage
The wing connections also utilized DB-9 D-Type connectors for the connection of the servos, when
the wing is slid onto the spar and mates with the fuselage the servo connections are made..
Fuselage Center Root section Wing Root section
Note: any fiberglass surfaces on the inside of the airframe that requires components to be bonded
should be cleaned with mild detergent and water to make sure that any mold release agent is
removed, and then scuffed with medium grit sandpaper in the area of the intended bond to
promote adhesion prior to applying the adhesive.

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Pneumatic Landing gear
General
The landing gear are pre-installed from the factory; it is recommended that the all retract units
should be removed and inspected for air leaks. This is easily done by submersing the retract unit
in a pan of water and applying pressure to each of the cylinder inlets while maintaining pressure
see if any air bubbles are detected. If leaks are detected they should be corrected by
disassembling the cylinders, cleaning, and applying O-ring lube, then reassemble and re-test.
Check the function of each gear with a hand pump or other suitable air source while they are
removed from the airframe. Make sure the extension and retraction of the gear is smooth before
final installation. The prototype unit needed some slight adjustment “filing” of the trunions” to
remove interference fit, see photo. Additionally check for free rotation of the wheels on the axels,
the wheel bushing will require lubrication or even may require reaming of the I.D. of the bushings
to create a better fit.
Step 1: Nose Gear
Remove nose gear from fuselage and perform leak checks as describe above.
After performing the above checks, assemble the steering servo into the nose strut steering
bracket as shown using the supplied mounting hardware. The output shaft is mounted
away from the strut.

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Using a receiver or servo driver find servo neutral and attach a suitable double sided
servo arm perpendicular to the servo making sure to tighten the servo arm screw.
The threaded rod supplied with the kit was 2-56 style all thread and clevises as shown
in the photos, it recommended to change these to 4-40 parts.
Step 2: Main Landing Gear
Remove main gear from wings and perform leak checks as describe above.
After performing the above checks, reassemble the main gear back into the wings using the
supplied screws or replace with builder supplied optional allen head bolts and blind nuts.

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Step 3: Forward Fuselage
Once the nose gear and servo assembly is completed, install the retract unit back into the
fuselage , prior to installation place a very small dab of thin CA into the mounting screw
holes first if using the factory provided sheet metal type screws.
Airline routing should be neat; it is recommended that the pneumatic valve equipment be
installed as far forward in the fuselage as possible. The prototype was built utilizing a Jet
Central electronic dual action valve for the retracts and a Jet Central electronic single
action valve for the brakes. Remember to keep equal lengths of air lines when creating the
right and left side run to the retracts and brakes to ensure even operation.
The Dolphin is supplied with brass airline connectors, the prototype used the male end of
the fittings glued into the fuselage at the wing junction for easy wing connections.
The female ends were left loose with extra length of tubing protruding from the wing halves.
A 1:1 scale drilling template and C.C fixture was created to locate the male connectors in
the wing root area of the fuselage and can be found in Appendix A of this manual.
BatteryMounting
The choice of the battery technologies to be used is up to the builder’s discretion. The goal of the
build was to achieve proper G.C. without the need to add dead weight. The prototype model
required that weight needed to be located as far forward as possible to achieve the proper C.G.
To achieve proper balance, two 5000 mAH LiPo hard case packs were used; one for the ECU, and
one for the receiver. A voltage regulator was used to create the required voltage level for the radio
system.
It is recommended that the batteries are mounted in a position to allow for easy removal for
charging and maintenance no matter what technology is used. There are many methods available
to secure the batteries, a few include mounting with adhesive backed Velcro™ or using zip ties
such as ty-raps on removable mounting plates etc. It is the builder’s discretion to provide the
proper securement method to ensure safe operation, maintain proper C.G., and allow quick access
in case of battery emergencies.

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Optional Battery Box
The prototype was constructed using two lite plywood battery boxes; these allow quick
removal of Li-Po batteries for charging and maintenance and provide a method for
achieving correct C.G. balancing without the need for added dead weight. The battery
boxes are longer than the LiPo battery’s, this allow adjustment for the C.G. by placing foam
spacers in the box to set the battery position.
The components can be cut from the templates in Annex A from 1/8” lite plywood. Lite-ply
is very strong when constructed into shapes such as the box.
Assemble the battery boxes using CA, see photo for detail.
Trial fit the battery box through the front former, if there is interference open up the area
using a Dremel tool or file.
After establishing a good fit, Hysol the battery boxes in place.
The batteries are held in place with a ¼” wood dowel that is positioned in the front of the
battery box, the dowel is held in position by servo screws, see photos below.
Step 4: Fuel Tanks
If your model is provided with a factory plumbed fuel tanks it is recommended that you
disassemble and inspect the tank hardware. The process used to cut the tubes at the factory may
leave behind a ridge that constricts fuel flow and could result in excess tank pressure / restriction
and leakage.
The author recommends that the factory supplied brass tubing should be replaced if it is not at
least 3/16” (4.76 mm) in diameter. Additionally fuel line barbs should be soldered to the tubing and
this can be achieved by cutting ¼” (6mm) lengths using the next size of telescoping brass tube, i.e.
7/32 (5.5 mm), this will prevent the fuel line from sliding off of the brass tubing. This change will
require that the supplied metal tank fittings to be drilled to accept the larger brass tubing or can be

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upgraded to the Sullivan Aluminum stopper kit #S478 which includes the larger 3/16” tubing. It is
also recommended to use 3/16” Tygon™tubing or equivalent for all of the interconnections of the
fuel system. Finally perform a leak check on each fuel tank prior to installation; this short process
up front could save a lot of time later.
The prototype model fuel system was assembled connecting the three factory supplied tanks and
the one auxiliary tank in series, in this configuration it is imperative that the larger diameter tubing
be used to reduce the restriction developed in the fuel system. All fuel system lines should be
properly inserted onto the tubing and safety wire tied to prevent unwanted and potentially harmful
leaks.
Note: Restriction in the fuel system may cause performance issue with your turbine such as not
allowing proper full speed RPM, abnormally high pump pulse width numbers and or excessive
stress placed on the tanks while fueling the model. Stress on the tanks is due to expansion caused
by air not venting out of the tanks fast enough during fueling. Additionally fuel restrictions or leaks
on the suction side of the fuel pump can cause cavitation, leading to air ingestion in the turbine fuel
supply, ultimately causing a flame out.
Total Fuel System Volume of the supplied tanks with the prototype was 122 oz (3600 ml)
Saddle Tanks ea. : 37 oz. (1100 ml)
Main Tank: 47 oz. (1400 ml)
An additional 34 oz. (1000 ml) Auxiliary tank was added to bring the total volume up to 155 oz
(4.6L).
Note: the user supplied Auxiliary tank could also be used for a smoke tank if desired.
Larger diameter tubing and drilled out tank hardware, Fuel line barbs soldered onto the tubes

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Tanks for Production Model
Optional builder supplied 1 liter auxiliary tank; Nalgene P/N 2007-0032
Tank Assembly
When working with brass tubing components please follow the steps outlined below:
Use a small, round file or a #11 X-acto knife to remove the excess metal inside of the cut
ends of the tubes. You will need to inspect the ends of all tubes. Another good method is
to use a countersink tool to de-burr the tubing, as you want to create an internal chamfer.
Make sure to install fuel line barbs, checking the ends of the brass tubing to make sure any
sharp edges are removed that could potentially cut the Tygon tubing causing leaks.
When finished, make sure to blow out any metal fragments that may have been left behind
and clean up any sharp edges.
While the components are apart, or re-fitting with new larger tubing, check the fuel pickup
line for equal lengths in both saddle tanks. They should be long enough to reach the back
of the tanks without being so long as to restrict their ability to move to the top of the tank
when the aircraft is inverted.
Make sure the bends created for the vent tubes have not restricted airflow to any significant
extent.

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Check the Tygon for any nicks or cuts, secure to the tubing with safety wire to the fuel
clunks and the pick-up tube.
If the aluminum tank bung fittings have not been fitted to the tanks, the tanks will need to be
prepared. Make sure the entrance hole is large enough for the bung. Sand the tank in the
area where the bung will be fitted. It is a good idea to drill a series of small holes around
the periphery of the aluminum bung flange to promote securement of the adhesive. Finally
using Hysol, glue the bungs to the tanks allow time for a complete cure before proceeding
with the completion of the tanks.
Once the tanks are back together, they should be leak checked before installation in the
aircraft. Connect extra lengths of fuel tubing to the fuel and vent lines and submerge the
tank in water. Pinch off one line and gently pressurize the tank by blowing into the other,
looking for signs of air bubbles. If the tank shows evidence of air leakage around the vent
cap, tighten the screw and check again. If the fiberglass weave is leaking; repair with Hysol
or epoxy or apply a layer of glass cloth and epoxy resin.
Tank Mounting
It is recommended that the fuel tanks are mounted to allow for removal for future maintenance.
There are many methods available to secure the tanks, a few include mounting with adhesive
backed Velcro™ or tack glue using a few dobs of RTV.
SaddleTanks:
The saddle tanks are located as shown; it is the builder’s discretion to provide the proper
securement method to ensure safe operation.

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Optional Mounting:
The method used for the prototype utilized plywood mounting brackets; templates shown in
Annex A may be used to fabricate them if this mounting method is desired the following will
guide you through the steps.
The plywood tank holders shown can be fabricated from the supplied template in Annex A
utilizing 1/8” (3mm) plywood. The saddle tanks use both a rear and front mount to secure
them. The front mounts also serve as a securement location for the main tank retaining
plate.
The circular mounts that bond directly to the rear of the saddle tanks utilize a blind nut that
is inserted on the back side of the mounts prior to gluing the mounts to the tanks. The rear
circular tank mounts are in two pieces to make a thicker section, joint the two sections
together, let dry.
Repeat this step for the other circular mount.
Once the tank mount assemblies are dry, bolt the rear circular tank mount to the rear
fuselage former mount. Note: make sure that the bolt does not protrude past flush with the
blind nut when tightened, if so grind to fit flush. There is a front and rear mount for each
tank.
Trial fit the saddle tanks as shown in the following photo sequence, mark the area on the
front of the tanks where the front plywood mount attachments will be positioned, and also
mark the area on the fuselage where the front fuselage tank mounts will be positioned.
Sand the areas with medium grit sand paper.
With the fuselage mount in place use the hole in the saddle tank mount to mark the position
of the hole in the fuselage mount, drill hole and install a blind nut to the back side of the
fuselage mount.
Now the saddle tank mounts can be bolted to the fuselage mount.
Glue the main tank mounts to the front saddle tank mount as shown in photo, install blind
nut on bottom of mount, let dry.
Bolt the main tank bracket to each saddle tank mount; this will hold everything in place
during the gluing stage.
Once the surfaces are prepared, apply Hysol to the fuselage former tank mounts and to the
tank where the mounts will make contact.
Repeat step for the other saddle tank, let dry.
Rear Saddle Tank Mount Front Saddle Tank Mount with Main tank mounts
Main Tank Mount
Front Saddle Tank
Mount
Rear Saddle
Tank Fuselage
Mount
Rear Saddle
Tank Mount

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Front saddle tank mounts and main tank bracket
Main Tank & Auxiliary tank:
The main tank is located as shown in the photo; it is the builder’s discretion to provide
the proper securement method to ensure safe operation.
Front Saddle
Tank Fuselage
Mount
Main Tank
Retaining Plate

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Optional Mounting:
This step was developed for the prototype which was supplied with a 1400 ml Main tank
that was made to fit between the inlets. The author considered that this fuel capacity was
insufficient for a model with the require thrust class turbine of this size, so it was found that
an additional 1000 ml rectangular auxiliary Nalgene tank would fit nicely under the inlets
and the main tank could be position on top of it. A main tank floor was developed to be
positioned above the auxiliary tank. The auxiliary tank could also serve as a smoke tank if
the builder decides that the factory supplied tanks have enough capacity.
Since the development of the prototype and based on the feedback from this process, the
factory has developed a larger main tank; however, it was too late to include photos or the
steps for mounting in this manual.
If you choose to use the mounting system developed for the prototype; the following will
guide you through the steps and may be adapted to the larger main tank supplied by the
factory, however it would need to be determined if the optional 1000 ml rectangular
auxiliary Nalgene tank would fit.
The plywood main tank retaining plate and main tank floor shown can be fabricated
from the supplied templates in annex X utilizing 1/8” (3mm) plywood. The saddle tanks
use both a rear and front mount to secure them. The front mounts also serve as a
securement location for the main tank retaining plate.
If using the optional (Builder supplied Nalgene tank) trial fit the tank into the fuselage, this
will be used as a position guide for the main tank floor.
If not using the auxiliary tank skip the step of mounting the main tank floor, and set the
main tank directly on the fuselage floor.
Position the main tank floor on top of the aux. tank; mark the inlets where the floor will be
bonded, sand the inlets for a good glue joint bond.
Hysol the main tank floor between the two inlets as shown in photo and let dry.
The main tank retaining plate can now be bolted to the saddle tank bulkhead mounts as
shown in photo. Note the main tank retaining plate will also work if the aux. tank is not
used, it is recommended to use Velcro on the bottom of the main tank to the fuselage floor
if omitting the aux tank setup to prevent the main tank from sliding forward at the bottom.
Main Tank
Floor
Main Tank
Retaining plate
Optional Aux Tank
Floor Glue
Joints