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I used to received many question from beginners who wanted to build long range fixed wing about which platform to choose for long range flight both for FPV and UAV purposes.  Today more people started jumping into fixed wing flying aim to fly beyond 35km and more where multi-rotor platform are at disadvantages due to their nature flying to 'fight gravity' which wasted much power to propel up in the air unlike fixed wing that float with the help of mother nature through horizontal airflow. With today latest updated technology such as improved high capacity lithium-ion battery, modern LRS radio system, digital FPV videos system (for FPV), compact size electronic hardware, reliable BEC/PDB, improved open source flight controller system (Ardupilot/iNAV/MultiWii/etc) and efficient brushless motor going for long range flight is more achievable than what it used to be back before year 2010.  Plus most of the build components are now cheaper and accessible via online market just a mouse click away on the screen.  By today long range flight standard on any fixed wing platform can fly on average 20km one way trip on basic build, but professional builder can get up to 35km and more which total up between 70km to 110km total mileage flying only on a single 18650 size li-on battery pack on average 1100mm wingspan model.   There's a lot of factor taking into account what makes it able to fly such distance but one of the 60% contributing factor would be the type of platform used.  In this guide article i would be talking about two type of flying platform that are popularly used for long range flight; Conventional tail plane and Delta flying wing.

• Conventional tail plane (normal fuselage + tailed plane):
  Is a flying platform with elongated center fuselage and most notable a tail that holds rudder, elevator and V-tail control surfaces which allow better leverage on pitch and yaw control.  Has landing gears and motor + propellers can be located either front of the wings/fuselage as 'Tractor' configuration or behind the fuselage as a 'Pusher'. This 'conventional' platform are the normally seen daily on our aviation scene like civilian and military aircraft.  So if average joe or jane thinking about what a plane would look like this would be it. 

• Delta flying wing:
  A flying wing is a tailless fixed-wing aircraft that has no definite fuselage.  For short its just a piece of wing that flies.  The wing design is usually swept back or in delta shape almost triangular like.  Almost looks triangular but wide and flat.  Delta shaped wings are the most popular choice for long range flight. Majority will have a dihedral wing tips and have either one or two vertical stabilizer fins to keep the flying trajectory straight.  It only have two movable flight controller having one on each side of the wings.  These are called 'Elevon' control which represent a mix of aileron and elevator control.  Since it doesn't have any rudder that only way to yaw or turn its to 'banking' the whole wing during flight on aileron and 'yank' the elevator to turn/yaw....in short we called 'bank & yank' flight control.  If you've seen my long range Youtube video on my UAV Wing Wing Z-84  that's is a delta shaped flying wing.  Compartment for electronics hardware, battery and etc are usually located in the mid slightly bulk section of the wing section.  Motor and prop configuration has always been a 'Pusher' type where they are attached behind the wings as mode of propellant.

Let's start with a short history on fixed wing FPV/UAV flight; Modern fixed wing as UAV has been around since 1935, it was a De Havilland DH.82B Queen Bee aircraft used as a low cost radio controlled drone developed for aerial target practice in United Kingdom Royal Air Force military. Then first 'FPV' (First Person View) flight started in 1943 by Boeing and U.S. Air Force with the BQ-7 aircraft with an autopilot system.   Only in 1973 Israel's Mastiff and the IAA Scout series of UAVs seen progress mature autonomous flight technology in action.  In year 2006 the FAA have permitted the use of drone in civilian airspace for search and rescue during Hurricane Katrina in US.  This events have led new ideas to create commercial and consumer drone for mass market to take advantage of military UAV technology. Unfortunately since most average jane/joe consumer unable to fly a fixed wing plane a multi-rotor platform that takes off vertically like a helicopter with aided stabilization was introduced which subsequently  came 2010 when PARROT introduced AR-DRONE a consumer first multi-rotor. DJI comes later with first PHANTOM multi-rotor series in 2013.  Unfortunately after nearly a decade after first consumer drone was introduce neither company able to deliver out of box fixed wing UAV/FPV for long range use because such capability is something normal people can't handle which is why that spiny 4x to 6x~8x spinning rotor easy VTOL continue to serve general drone enthusiast market.  Long range fixed wing flight have been active and successful for many years with many useful purpose running behind the scene when average multirotor 'drone' enthusiast still clamoring struggle to improve its limitation to fly longer range. Which is why some decided to outside the box and embrace the classic fixed wing platform as true long range drone flight.  We'll lets cut the chase and go straight to our discussion on 'Conventional' and 'Flying Wing' platform shall we.

Technical aspect and build

Both platform can have the same electronics build;  flight controller hardware, power modules, batteries pack, onboard camera, FPV hardware (VTX, OSD module), radio RX, telemetry system, ESC and brushless motor unit.  However since both have different wing configuration and physical flight control surfaces both may uses different amount of servos and BEC requirements to operate:

• Conventional tail plane:
  Conventional plane have more flight surfaces to operate; normal it has both left and right aileron, tail rudder and tail elevator or sometime it runs on V-tail configuration.  Overall on average it requires minimum between 3x (for shared aileron) to 4x servo to operate all its flight surfaces.  Bigger size plane with a wingspan beyond 1400mm can have up to 6x servo having extra 2x for flaps to slow down the descent for landing.  Because it has more servos it requires high amp BEC module ideally rated at 5V/5A to power all 5V powered devices on board especially those multiples of power hungry servo so the current can be sustained during long range flight without hitting 'Brown Out' where current supply hits the bottle neck.  Current consumption (A) on servo hit its peak especially during turbulent windy weather where all servos started to sway/move actively to stabilized the plane especially in STABILIZED, CRUISE, AWB, AUTO and other stabilization modes.  Which is why conventional tailed plane need reliable and bigger amp BEC module. Conventional platform normally has wheeled landing gear  not just for landing but also as height clearance to place lower mounted camera gimbal placed between or aft the landing gear. Propeller and motor thrust configuration can be both 'TRACTOR' and 'PUSHER' prop which every suites well for the builder.

• Delta flying wing:
  Usually have simpler flight control surfaces called 'Elevon'; both side of wings have 2x servo that can act of mixed both aileron and elevator together. So it doesn't have any rudder.  The only way to yaw or turn during flight is by banking on its side and pull the elevator to turn/yaw hence what we called "Bank & Yank" maneuver which is popular flight control method for fast platform like EDF jets or combat wings.  Almost 98% of the market Delta flying kits are made to have a 'Pusher' prop configuration where motor and propeller located behind end of the platform.   The compartment for placing the electronic hardware, battery pack, GPS, FPV equipment and etc are extremely compact and located in the middle section of the wings.  Getting the right weight balance is harder because any flying wing is very CG (Center Gravity) sensitive.   Take lots of trial and error to find the right CG point under its wing. Building on delta wing usually are 30% cheaper than conventional tail plane due to less amount of servos, wiring and BEC requirement.  These platform are popular for being simple, cheap, robust and efficient in power consumption.
  
  

Carrying capacity

• Conventional tail plane:
  Conventional plane usually have more space to carry hardware and extra payload because it has long elongated fuselage with more space internally placed under the main wings.   Popular FPV drone planes in the market such as SKYWALKER, SKYHUNTER, BIXLER, TALON, VOLANTEX RANGER and other tailed fixed wing have bigger fuselage void to house all the hardware and payload necessities. Most of these planes are 'high winged' which mean the wings are placed higher above the fuselage center gravity to allow the heavier part such as fuselage and its inner gut to act as gravity pendulum to stabilized the plane like clock pendulum.  Which is why this platform is very popular among beginners and automated payload deployment (autonomous cargo delivery) flight.  However it needs bigger battery capacity to provide extra power to thrust the plane with its extra weight. It could carry extra 20%~30% weight beyond the permitted 'wing loading' capacity depending how efficient the main wing airfoil design.  For example my 950mm wingspan ES Drifter UAV build have manufacturer recommended flying weight of around 615gram but it final flying weight for my build was 850gram still able to fly stable during autonomous flight.

• Delta flying wing:
  Usually doesn't have much internal capacity to carry 'payload'.  Its just enough to carry flight system, battery and other necessity to operate the platform.  Have about 30%~40% less internal space than the conventional tailed plane due to absence of bulk fuselage which means hardware setup have to be compact and as flat as the overall wings horizontal surfaces.  The build weight and placement of the hardware have to be very calculated and careful because the center gravity (CG) is very sensitive on flying wing.  Choices of battery form factor also very restricted since there not much space to store unconventional size battery pack on such a flat profile wing.  However flying wing platform was never a popular choice for automated payload deployment (autonomous cargo delivery) flight due to its overall aerodynamic flat wing design which no place to carry such cargo load.  Since its very sensitive to weight its recommended to fly with flying weight recommended by manufacturer spec else max extra 10% weight tops, anything higher will cause severe unrecoverable stall.
  
  

Launch and landing

• Conventional tail plane:
  Conventional plane can be launch with wheeled landing gear or hand launched (can be a bit tricky).  Landing accuracy on conventional plane is easily achieved due to the fact it has tail rudder to yaw rather than bank and turn at last minute.  Usually this is the best and easiest platform to fly for any beginners and intermediate pilot. However it need proper flat runway to land, net system to catch or else simply belly landing on the grass provided no camera or load strapped under the fuselage belly.

• Delta flying wing:
  Majority marketed flying wings doesn't have landing gear so mostly take-off via hand launching...never was and never will.  It can be tricky, dangerous yet requires skill to launch by hand because operator/launcher's hand or fingers may caught in its way from the fast yet sharp spinning propeller on the rear of the flying wing at full throttle if not caution.  Landing can be tricky too because it doesn't have rudder to yaw/turn around so pilot/operator need to do  "Bank & Yank" maneuver in the controller to guide its landing position and knows when to 'flare' to slow down before it touch the ground.  It can be catch by hands if the operator are good at it.  Usually this platform ideally to be operated by experience pilot/operator.  Regardless the hazard and level of difficulty operating the flying wing it still the best platform for long range flight in term of endurance and technical simplicity.   The overall advantages for a flying wing is any bad landing and launches would not cause any damages or total it because majority wings platform are build durable and resilient to any crashes.  The biggest advantages of Delta flying wing over Conventional tail plane is that it can be launched and land at very tight and narrow location regardless of terrains or geographical obstacles since its basically hand launched and land into bushes or hand catch (if the flying wing size is handful enough having under 1100mm wingspan). 
  
  

Flight characteristic, performance, endurance & range

*Note: Below are the information given both model have the same mass, power and weight:

• Conventional tail plane:
  About flight characteristic naturally once in the air these conventional platform with high wing, fuselage and tail will fly more stable and upright all the time regardless of any rough weather it encounter since its center gravity where the heaviest part of the plane located below the wing in the fuselage.  So it flies with a heavy 'pendulum clock' below the wings that keeps it up right which makes it an ideal for aerial photography and 3D mapping photo capture with gimbals below its fuselage.  With its long 'plank' like main wings it could capture more airflow under its wings for efficient lift which enable it to carry much heavier onboard load/payload or cargo.  In short its a heavy duty plane and floats easily with its max weight... it flies like a kite in heavy wind. However like a kite its survival is at the mercy of bad wind condition, it could slow down the forward thrust, hit by cross-wind causing it to fly like a  'crab' flying sideways or simply float stationary until enough thrust able to exit its own trouble.  This is all because the entire wings, tail and fuselage generate much wind friction to keep it from moving forward.  But at the same time being slow also mean stable onboard video/photo capture or any stable imaging capture task especially since it flies very upright position all the way.  Stall characteristic can be a bit a mixed bag but it all depends on the wing tip designs.  If the plane weight are overloaded; wing tips design that have dihedral design more likely to stall more than straight stub wing tip design.  Planes that have elliptical or round sweep wing tips tend to fly a bit faster like the FPV TALON platform.
  
  When it comes to performance, endurance and range the this platform is average and the Conventional tailed plane placed a spot behind Delta flying wing because it as mentioned before the whole fuselage is a 'wind friction'..a major wind drag overall that slows down speed, consume lots of power to propel forward and get tossed around by cross wind easily.   Flying in a bad weather is a 'no no' because i used to lost one Ardupilot powered autonomous plane in heavy cross wind during lunch time...last seen was at 11km via telemetry indicator and gone forever never to return home. Under the same cross wind condition my Z-84 was able to penetrate the wind easily and complete the mission in one hour.  In term of range with the same mass and power on board the Conventional tailed plane can only cover 30%~40% less distance than Delta flying flying does.

• Delta flying wing:
  As for its flight characteristic its flies straight like a rail because its doesn't have huge 'wall' side area to get pushed around by cross-wind.  They do loose small amount of airspeed and altitude during banking/yaw/turning because the  "bank & yank" maneuver causes the whole wing to tilt on its side between 15 to 45 degree banking bleeding out wing lift effect on either side of the wings.  It takes a bigger radius to turn than conventional tail plane that have rudder sometimes would take about 50 meter to 60 meter turning radius for average 1000mm wingspan just to turn safely with safe banking angle at 15 to 35 degree at cruise speed without causing it to stalling or one side of wings dips too much.  Note; this is what i always do to test my newly build UAV wings to see how much angle could it take before it become to severe to fly safely in autonomous mode.  Like any flying platform flying wing do stall when either side of the wings dips too much but they recover easily in a few seconds regardless as long the flying weight on board build within wing loading permitted specification.  If it stall it probably drops at 10 meter altitude altitude and recover back in control easily back on track,  For a conventional tail plane it may went into full spiral any may take half of total of flight altitude yet longer time to recover.  So when it comes to stall a flying wings is very resilient which is why they are well enjoyed by R/C flyer for combat wings event for air battle carnage fest.
  
  For its performance, endurance and range the Delta flying wings always remain superior against the Conventional tailed plane because of its flat and less wind resistance surface making it consume less power when thrust forward.  Plus its able to traverse various harsh weather mother nature can throw at it wind, rain, thunderstorm and etc my Delta wing made it home with low thrust as shown in many of my flight videos with Z-84 on my Youtube channel.  The distance its cover as per-battery power consumption is almost 2x and 3x longer distance than conventional tailed platform too.   This is where the wing is much preferred among long range enthusiast.
  
  

Radio antenna, GPS module isolation and RF noise factor

This is about placing the radio RX and radio data telemetry antenna on the flight model and keeping it away from noisy on board hardware such as PDB boards, servo or BEC RF noise.  Any radio receiver and transmitting antenna can easily pickup any RF noise on board.

• Conventional tail plane:
  Due to its long elongated structure on both fuselage/tail and main wings its very easy to put the antenna at very tip end of the structure to keep it away from onboard electronic hardware that emits RF noise such as BEC/PDB, servos, ESC and etc.  For example i always placed my 3DR radio telemetry antenna on the end of the tail section far away from onboard electronics, tail servos like elevator and rudder are always located in the front fuselage linked to their flight surface via long push rods so it will not interfere the antennas. GPS module can be fitted  on the far side of the wings away from fuselage full with RF emitted electronics.  Based on my experience building such setup i always get a got full 8 to 11 satellite 3D lock on the GPS after 8 second boot and also a good clean 11-25km straight line telemetry data beam to the ground station when antenna is at the further side of the plane tail section.

• Delta flying wing:
  On flying wings placing the GPS module and antenna can be quite challenging because everything is crammed together in such a short flat fuselage and RF interference can easily reach the GPS and antenna on board.  433mhz data telemetry antenna full wave length is already enough to wrap around on my 845mm Z-84 wings parameter making it harder to isolate from RF source sitting to close to nearby servo, GPS, ESC, BEC and motor.  However it could be solve if you own a bigger size wings such as the 2000mm ZETA FX-79 BUFFALO wing which is actually the Z-84 big brother that have ample size for antenna isolation...unfortunately is way too big and heavy for average long range drone hobbyist because i've been there and done that with such wings.  On Z-84 i only can get a good data telemetry at straight line distance around 9km~12km average before it gets cut off and fly autonomously in radio silence mode.
  
  

Survival on low voltage during UAV (autonomous) flight. (non-FPV)

• Conventional tail plane:
  The advantage of conventional platform is its ability to float longer (stay in the air) because its long 'planky' style wing especially at high altitude and still able to carry abundant weight.  So it pretty much flies like a kite since it traps lots of wind pressure under its wing and also generate too much wind friction causing it to stay slow yet stable which makes it good for aerial photo/videography or mapping. Having a good wind is good to stay afloat but sometimes it leads to another disadvantages.  Since the whole fuselage create wind friction it need lots of thrust to propel from motor and propellers to move forward, you'll need a steady amount of battery voltage to maintain 'volt per-rpm' (KV) rating to keep the motor and prop running.  Unfortunately during longer flight battery capacity will drain over time and voltage rating will go down too before reaching cut-off level.   So if the motor and propeller started to slow down the plane might just move slower or at worse scenario just enough thrust to float stationary catching wind and flow down steadily.  Sometimes if the fuselage is long and hit by cross wind on its side the plane may fly crab like side ways if the motor/props runs at reduce thrust.   This is why lots of conventional tailed plane fail to return home because of insufficient thrust due to battery voltage started to drop down.  This happens to my Ardupilot (APM) operated UAV SKY VICTOR (FLY INSPIRED) aka BIXLER which fail to return home during its flight into windy weather...yes, it went MIA (Missing In Action) after last turning point on return home with telemetry data shows it started to crab side ways on low voltage then slowing to almost a halt.

• Delta flying wing:
  Due to its overall sweep design delta wings are naturally built to penetrate windy condition and able to keep moving forward with bare minimum amount of thrust because it frontal whole wing surface section have less wind friction surface to encounter unlike conventional fuselage/tailed plane.  It could also float longer in the air provided its flying weight build lighter before hitting wind loading weight limit.  Flying wing are known to be able to fly with just 10% to 30% amount of thrust from motor/propellers spin which is why they are popularly used for powerless slope soaring and combat wing fight among R/C flying enthusiast at windy slope.  This is why i love to fly my WING WING Z-84 as autonomous long range platform than my standard conventional tailed plane because it already proven over many of my flight video that it could fly extremely lower amount of thrust when the battery is already hitting li-on battery 'cut-off' level yet survived the harsh windy and rainy weather mother nature can throw at. 
  
  
  

Durability, reliability and maintenance

• Conventional tail plane:
  Base on experience working with conventional tailed plane both on FPV and autonomous flight such as on my VOLANTEX RANGER, SKYHUNTER (Twin tailed), ES DRIFTER (both FPV and UAV type), SKY UAV/VICTOR (Bixler clone..MIA), HK BIXLER and others they usually require frequent maintenance and some parts replacement every cycle of if it started to show some wear.  For example every 300 to 400 cycle hours on the coreless brushed 9g mini servo on either side of aileron or rudder will show sign of wear through internment twitching at random times and sometimes may 'burnout' internal BEC if immediate replacement not done.  Servos wear a lot on conventional plane because it has to handle much weight and wind pressure from below (aileron) and side ways (rudder), it worn out faster if it used as a flaps.  But the most common problem has always been landing gear constantly bent or broken after caught tangled with grass or hit rough surfaces which is more common happen to conventional plane owner including myself.   Some opt without landing gear for more smoother belly landing on the grass provided the camera is installed on upper front of the fuselage.

• Delta flying wing:
  After operating my UAV Delta flying wing for 5 years (2016 till 2021) on weekly basis with the same battery pack over various harsh weather, rain flooded electronics onboard, into distance remote location and logged hundreds of hours amazingly both of my UAV Delta flying wing (Z-84 series) have no maintenance or part replacement at all.  Plus it still uses the same 4s 18650 3500mah battery even after 5 years of use. No crash, no dents just normal under belly scratches when landing on cemented/tarmac surface.  Due to its robust, simplicity, easy to launch and extremely portable 'go to' UAV plane this one has been my number choice for long range adventure plane that doesn't give much technical problem other than me sitting for an hours awaiting for its return flight from completing its glorious autonomous mission.
  
  

Popularity of use

• Conventional tail plane:
  Conventional tailed plane are most popularly used for aerial video/photography, humanitarian aid, property & civil development, delivery services, localized search & rescue mission and also as expandable research & development experimental aircraft model where it concentrated on flying more short duration and localized range.  This is favorable platform of choice because it could carry heavy high quality camera (4K/8K) with stabilization gimbal under the fuselage and also able to to mount payload 'gripper' mechanism for dropping delivery cargo at drop point for autonomous mission or for 'cloud seeding' creating rain in some part of the world.  Conventional tailed platform also extremely suited by R&D drone company to experiment many multi-role flight such as implementing VTOL flight (quad-copter from on fixed wing), take-off and land from water and other features since its a very stable and upright flight.  However it need bigger space to take-off and land as mostly wheeled landing gear have fragile hardware between under the fuselage like cameras and etc.  Plus if it crashes it can be easily write-off straight away rather than simple fix due to complex attachment such as main wing, fuselage, vertical stabilizer (tail rudder), horizontal stabilizer (elevator) and landing gear all bind up together.  They can be extremely handful to transport too which is why they are less frequently use and expensive to operate unless needed.  For normal drone hobbyist this is a great startup for FPV platform since it could fly stable and tame enough for beginners to fly.

• Delta flying wing:
  Flying wings are most popular and commercially used by many professionals in agriculture, farming, forestry, maritime sea surveillance, civil engineering (road works and piping) industries and environmental monitoring/activist due to its capability to cover large distances over unpredictable weather.  It carries simple mission to 3D mapping the area or simply scanning anything on the ground via static camera/sensor on board especially though center cavity holes where it houses the camera and sensor in the middle.  It also can still carry camera or sensor in front of the nose section but not as heavy duty as the Conventional tail plane can.  Flying wing are much favor for these industries and professional user because its ability to repeatedly use daily, launch and land anytime in narrow and unfavorable places such as in bushes, forest, off from windows or moving vehicle yet still able to survive multiple crashes in hazardous condition or mishandled by operator because flying wing platform mostly build in one piece of structure and can be easily fixed or even fly back with dents and bumps on its wing surfaces.  For serious drone hobbyist this is a good platform for both FPV and UAV platform specifically for efficient long range flight focusing on conserving battery power/energy while able to reach high altitude and range with less effort.  Plus for those who seek for durability, simplicity and re-usability over time the flying wings always been a winner in this category.
  
   

Video

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Support group/articles:

Places where you can find help and resources related to this article:

• Rcgroups fixed wing builder FPV/UAV discussion board:  https://www.rcgroups.com/aircraft-electric-fpv-861/
• DIY Drones website:  hhttps://diydrones.com/
• Open source flight automation - Ardupilot:  https://ardupilot.org/
  

Summary

If you wanted my honest opinion which one is the best for 'power efficient' long range FPV/UAV flight between two platform given that both have the same mass, battery capacities and thrust power then i would choose the 'delta flying wing'  platform a thumb up because i've been in and out building and flying between two of these popular platform which results my conventional tail plane collecting more dust than my daily active flying wing. Thus said if you still wanted to be adventurous and pushing it limits beyond the edge to explore outside the box for now obviously the flying wing is your best bet.

Above statement is based on my hands on experience however there's no right or wrong in choices going either both platform, its all depends what you wanted to achieve and comfortable at operating the aircraft model. As for today i still flying rigorously my favorite Z-84 delta shaped flying wing while still keeping my conventional tail plane the VOLANTEX RANGER and ES DRIFTER ULTRALIGHT (UAV version) for future special 'localized' mission (eg: aerial photography/3D mapping) which suits them best.  Ideally having both types is an advantage for muti-role flight when needed.  The only moment when i used Conventional tailed plane the most is when i do FPV flight because having a tail plane (rudder) makes it more easy to maneuver manually in the air in more precision matter and enjoy stable FPV view from cockpit POV.  At the end of the day having both type of platform give more alternative ways and diversity to enjoy fixed wing drone flight.... the choices is up to you.