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Help! Need Help to Build 1524 mm (60") Search And Rescue C-130 J-30 LRF/FPV

#1
I've sat here waiting to buy equipment for my two Standard size DTFB planes with an idea in my head. I want to seriously build a usable Search and Rescue aircraft with the following capabilities.
1. Large Cargo Aircraft/Heavy Lifter.
a. Large Usable Cargo Bay.
b. Controllable Multiple Cargo Pod/Palate Drop System. (Servo operated one-at-a-time drop system).
c. 6.6 lbs./3 kg. Cargo Weight Above Plane W/Full Equipment Load-Batteries.
2. Long Range Capable.
a. Time in Flight. (Push Flight Envelope to 30+ minutes).
b. Distance Controllable. (Flight/Video in Miles/Km Distance)
c. Easy Battery Access for exchange for continued flight missions.
3. Easily Built/Repairable Airframe.
a. Sectioned for ease of transport. (Two Part Wings/Nose-Cockpit/Tail-Rudder-Elevator/Main Fuselage)
b. Light Weight and Strong.
c. Built in Survive-ability and Serviceability. (Rough Weather Capable.)
d. Strong Large Wheel Landing Gear for Rough Terrain Take-Off/Landings. (Nose gear need not be servo controlled).
e. Aerodynamic Blended Wing Attachment. (L-lock leading edge, Twist-lock trailing edge.)
f. Separate Controlled Cargo Bay Door/s.
5. Video Systems.
a. FPV W/OSD, Switchable to 2 Auxiliary Cameras, Wide-Angle Down, Cargo Bay Check View. (External Cams Day/Night Vision)
b. Auxiliary Monitored Day/Night Vision/Thermal Down View Cameras.
c. Internal and external recording capabilities of all cameras.
6. Lighting Systems.
a. Standard Navigation Lights W/Strobes.
b. Landing Lights Switchable to Off. (Must be bright enough to assist FPV VFR/OSD Instrument Landings)
c. Internal Cargo Lights for Drop Control/Verify Drop.
(d. Possible Belly Mount Search Lighting, including Ultraviolet Night Vision assist.)
7. Power Hub power control system.
a. Output for 4 motor system.
b. Output for servo system.
c. Output/s for camera operation.
d. Output/s for Lighting System.
e. Master Battery Off/Safety Switch, W/Flagged Insert Key. (Large Red Reflective Strip for Quick Visual Reference).
(Listing of Aircraft Requirements will be adjusted as needed/suggested)

The C-130 J-30 is chosen at this time due to it's service record of foul weather flight capabilities, and cargo capacity. This SAR aircraft will be flying under 400 ft./ 121.92 meters altitudes, more than likely tree top level per local area typography and vegetation. To fully assist in SAR missions the aircraft will be flown out of Line Of Sight. Thus such items as Down Aircraft Beacon/Alarm will be installed. Although Flight Crews will coordinate with Ground Search Teams to increase Line Of Sight Command Location and Search Team Awareness of the craft and it's flight path/pattern.
Flight Crews should consist of a 3 person team, Pilot, Spotter/Navigator, Search Monitor. They should know the aircraft and all of it's systems inside and out. Previous Air Crew Operations knowledge and training a plus. The Ground Station must be portable, and protected via tent or trailer unit during foul weather/night operations. The Flight Crew must be in constant communication with SAR Command, and be able to relay Air SAR Operation capabilities for mutual understanding of level of assistance system can bring to the op.

The main reasons for such a system build are as follows. A Long Range Extended Flight Time Fixed Wing Remote (UAV) in this configuration brings more eyes in multiple types of view (Day and Night Vision plus Thermal), and multiple cameras on one platform. OSD (On Screen Display) systems add GPS coordinates for plotting location of lost/injured persons, assisting ground crews in plotting safe and timely access routes to victims with recorded over-flight video replay, or live-view. In addition, these aircraft will have the capability to drop Emergency Supply Packages to lost/injured victims at time of discovery, or afterwards if conditions change. These ESP's can include many things such as location beacons, space blankets, water and energy food rations and first aid kits. Multiple ESP Drop Units provide for multiple person aid at one site, or multiple sites should a group have split up, or multiple individuals or groups be involved. ESP's can also be customized on the fly to assist Ground Search Units in extending their search abilities without need to return to base. Batteries, food, water, equipment for repelling/climbing, splint kits, hasty compact stretcher packs, micro-tents, can all be loaded and delivered quickly.

To answer one question this subject brings up. FLIR is located nearby in Wilsonville Oregon. I will be in contact with them concerning Night Vision and Thermal Imaging equipment. A local group know as "Roswell Flight Crew Team" operates FLIR Vue Pro cameras on quad-copters for the Portland Metro Fire Department. This is a local non-profit organization I will be also getting in touch with.

Any assistance will be greatly appreciated and notated during this build. I have given myself six months to have a base aircraft built for maiden flight testing. Of any organization I can think of "Flite Test Family" in my mind is the best resource for such an undertaking.
Ahead of time, I thank all of you. USCG_C130_Hercules.jpg
 

b-29er

Active member
#2
I've sat here waiting to buy equipment for my two Standard size DTFB planes with an idea in my head. I want to seriously build a usable Search and Rescue aircraft with the following capabilities.
1. Large Cargo Aircraft/Heavy Lifter.
a. Large Usable Cargo Bay.
b. Controllable Multiple Cargo Pod/Palate Drop System. (Servo operated one-at-a-time drop system).
c. 6.6 lbs./3 kg. Cargo Weight Above Plane W/Full Equipment Load-Batteries.
2. Long Range Capable.
a. Time in Flight. (Push Flight Envelope to 30+ minutes).
b. Distance Controllable. (Flight/Video in Miles/Km Distance)
c. Easy Battery Access for exchange for continued flight missions.
3. Easily Built/Repairable Airframe.
a. Sectioned for ease of transport. (Two Part Wings/Nose-Cockpit/Tail-Rudder-Elevator/Main Fuselage)
b. Light Weight and Strong.
c. Built in Survive-ability and Serviceability. (Rough Weather Capable.)
d. Strong Large Wheel Landing Gear for Rough Terrain Take-Off/Landings. (Nose gear need not be servo controlled).
e. Aerodynamic Blended Wing Attachment. (L-lock leading edge, Twist-lock trailing edge.)
f. Separate Controlled Cargo Bay Door/s.
5. Video Systems.
a. FPV W/OSD, Switchable to 2 Auxiliary Cameras, Wide-Angle Down, Cargo Bay Check View. (External Cams Day/Night Vision)
b. Auxiliary Monitored Day/Night Vision/Thermal Down View Cameras.
c. Internal and external recording capabilities of all cameras.
6. Lighting Systems.
a. Standard Navigation Lights W/Strobes.
b. Landing Lights Switchable to Off. (Must be bright enough to assist FPV VFR/OSD Instrument Landings)
c. Internal Cargo Lights for Drop Control/Verify Drop.
(d. Possible Belly Mount Search Lighting, including Ultraviolet Night Vision assist.)
7. Power Hub power control system.
a. Output for 4 motor system.
b. Output for servo system.
c. Output/s for camera operation.
d. Output/s for Lighting System.
e. Master Battery Off/Safety Switch, W/Flagged Insert Key. (Large Red Reflective Strip for Quick Visual Reference).
(Listing of Aircraft Requirements will be adjusted as needed/suggested)
...Would you like fries with that?

In all seriousness, this is a difficult project, and you're talking about a very high-end payload, so lets ask some follow up questions here:

1. What is the field condition. Is this always taking off of pavement, sometimes taking off of grass, or hand launch?
2. You want a 30 minute flight time, but do you want to loiter or get out to target? This will affect your motor and prop, as large pancake motors and low-pitch prop would sip fuel but not fly fast economically, where something like a 5055 with a 14" high-pitch prop would be great for long-range flying with a good airspeed.
3. What is the need for 4 engines?
4. What is the actual envelope for all components to fit into? like how big of a box do you want to fit all this into?
5. You want a cargo bay, whats the payload? You can fit 3kg of lead into a payload bay that can fit a 2l bottle, not 3kg of nerf footballs. How big is each individual item your dropping, or is that variable? What kind of size would you want minimum? Would a bomb bay be viable, or does it have to be dropped out of the back of the aircraft?

A lot of what you are asking is going to be more an issue of non-airframe components, but electrical, and shouldnt affect design. Example, the long-range radio could be mounted just as easily on your aircraft, or a nano skyhunter, depending on the system. Your payload is not part of the aircraft design outside of provisions for whatever gimbal system you want on it to mount on the airframe. Multi-camera switch to see if your payload has dropped is definitely not an airframe concern.

Hit me up with the answers for 1-5, and i'll see what i can help you out with.
 

PsyBorg

Wake up! Time to fly!
Mentor
#3
Things to also think about are total power consumption of all those add on electronics.

Then you also need to realize tree top level recon with anything not infra red is going to be nearly useless over anything but open field at that height as you will have to be moving too fast to stay in the air.

An example would be trying to spot pennies on the road by hanging your head out the window and looking down at the road while the car is moving at the speed limits for highway traffic.

Current Fpv gear will not have near enough resolution for SAR. You would have to carry something like the higher resolution filming gear similar to what DJI uses to transmit separate images from piloting imaging.
 

Keno

Active member
#4
Working on a C123 Provider FT type construction it has a 54 inch wingspan. I am using Peter's FT Guinea Pig design but adapted to have the appearance of the C123 and C130. I say go for the C130 it a great cargo plane 4 engine how could not like it, haul tons of cargo, sounds like a great project.
 
#5
Hey, this sounds like a really cool project!

You'd probably want to start out your avionics search looking at ArduPilot. It might have everything you need software wise - maybe.

I'm an electrical engineer and have a bit of experience developing UAV avionics. Right now I'm working on making custom hardware/software for my own UAV and have a build log here.

I'd also be interested in helping more closely if you want. PM me if you'd be interested in that too.
 
#6
Things to also think about are total power consumption of all those add on electronics.

Then you also need to realize tree top level recon with anything not infra red is going to be nearly useless over anything but open field at that height as you will have to be moving too fast to stay in the air.

An example would be trying to spot pennies on the road by hanging your head out the window and looking down at the road while the car is moving at the speed limits for highway traffic.

Current Fpv gear will not have near enough resolution for SAR. You would have to carry something like the higher resolution filming gear similar to what DJI uses to transmit separate images from piloting imaging.
Camera SAR is the HD Wide Angle cam system monitored by separate person at ground station. This would also include monitor of something like FLIR's Vue Pro Thermal Camera now in use on Drones.
 
#7
...Would you like fries with that?

In all seriousness, this is a difficult project, and you're talking about a very high-end payload, so lets ask some follow up questions here:

1. What is the field condition. Is this always taking off of pavement, sometimes taking off of grass, or hand launch?
2. You want a 30 minute flight time, but do you want to loiter or get out to target? This will affect your motor and prop, as large pancake motors and low-pitch prop would sip fuel but not fly fast economically, where something like a 5055 with a 14" high-pitch prop would be great for long-range flying with a good airspeed.
3. What is the need for 4 engines?
4. What is the actual envelope for all components to fit into? like how big of a box do you want to fit all this into?
5. You want a cargo bay, whats the payload? You can fit 3kg of lead into a payload bay that can fit a 2l bottle, not 3kg of nerf footballs. How big is each individual item your dropping, or is that variable? What kind of size would you want minimum? Would a bomb bay be viable, or does it have to be dropped out of the back of the aircraft?

A lot of what you are asking is going to be more an issue of non-airframe components, but electrical, and shouldnt affect design. Example, the long-range radio could be mounted just as easily on your aircraft, or a nano skyhunter, depending on the system. Your payload is not part of the aircraft design outside of provisions for whatever gimbal system you want on it to mount on the airframe. Multi-camera switch to see if your payload has dropped is definitely not an airframe concern.

Hit me up with the answers for 1-5, and i'll see what i can help you out with.
1) Field Conditions. As mentioned in 3 d / This will be variable, from pavement, gravel, grass, cut straw, snow. Anything i can land on with a 3" foam wheel or equivalent. Possibly general belly landing if needed.
2. Flight time. Normal SAR flight ops require flight to search zone, then a "Mow The Lawn" pattern flight watching and recording down view cameras. Once that grid is cleared, either move onto the next, or return for battery pack exchange, fly to next grid. Since requirements carry many variables on flight time, I will consult those in the know about balancing weight, power and equipment. Most aircraft are built and fly with a 15 minute flight time. I hope to increase this to a minimum 30 minute foul weather time, if not more.
3. In creating this system I looked for the best full sized design used in such SAR, heavy haul, long range, bad weather handling aircraft. Almost every such bird is 4 engine, or at least a Turbo-Prop Twin. Because of the high possibility of rough runway conditions, Overhead Wing Design and Multi-Engines uses smaller props mounted on the high wing avoiding ground FOD (Foreign Object Damage). And the size of my bird is also important. Even though it will be built portable by sectioning, anything much over a 5'/60"/1524 mm wingspan will take up to much room at SAR Command, or near there. Finding room to set up a Field Expedient Runway and being able to maintain it during SAR operations is also a key factor. Therefore...
4. The Cargo Bay is planned to be 5"/127 mm tall, 7"/177.8 mm wide, 24"/609.6 mm long. This does not include Cockpit/Nose or Tail/Rudder/Elevator section beyond rear cargo door. Plans are for the flat (mostly flat) tail area to extend forward to just behind the cockpit/nose. With this cross section, there will be ample room for avionics, power, camera systems. Avionics can by design be assigned space in the central wing area to include possible range extension secondary receiver near or in the tail section.
5. Having chatted with a couple of SAR personnel, the ESP's (Emergency Supply Packs) will be set up to be approximately the size of a 2 liter bottle or less, for the First Response Packs. The main objects will be a beacon/radio, batteries for extended operation of at least one cycle longer, small water bottle, possibly a first aid kit. The FR-ESP's will not necessarily be universal, but exchangeable to meet local conditions at the time and location of search. Follow up ESP's with specific equipment to meet on site requirements for victims and searchers are planned, as first stated.
Bomb Bay: This idea banged around, but was negated by the need for a solid fuselage floor for camera operations, and structural simplicity. In case of main landing gear problems/rough terrain issues, belly landing with bomb bay doors would mean a high level chance of serious damage to the aircraft. Support structure for such a system would also increase weight. I have also considered negating the cargo door, opting for using two servos to control the cargo release system, instead of one for the door, and one release. This will largely play out in the final aerodynamics of the plane, if removing the cargo door altogether will create to much drag, lowering flight time.
I hope this answers your questions. Please ask more if you feel I haven't answered these or you have further questions. I appreciate such thought provoking, so that I don't become narrow of focus on this project.
 
#9
I think maybe I should also post where my idea for this SAR UAV system came from. As a child I was fascinated by the fact my father served in the Air Force as a photo interpreter of high altitude high res images from the SR-71 and U-2. He returned to civilian life when I was quite young. Growing up my three loves were Planes, Trains, and of course Automobiles. I grew up along with the Transistor. I loved electronics, mechanics, and the exploding realm of Electro-Mechanics. This was the early sixties. I wanted to be a "Imagengineer" for Disney. Fresh out of high school I found myself dressed in green from head to toe. I served in the Army from 1976 to 1983, Reserves-National Guard till 1992. My first permanent duty station was Fort Bragg, the home of the 82nd and 101st Airborne. Thus I became quickly familiarized with my newest friends... the C-130 Hercules, C-5-A Galaxy. In that day the saying was, "Your a solider first." Thus something called TDY or temporary duty. I was introduced to the fun times of equipment drops, high and low altitude via Herc's as we called them. Palatalized loads with full parachutes or drone chutes. Next was my overseas tour in Korea. I bought and flew my first RC plane there. A simple .45 gas RTF. I was hooked... until the perimeter guards shot it down one night. I then bought a boat. :p
Jump ahead to a year ago when I found Flite Test through YouTube, and found DTFB planes! One idea led to another, and now my Fixed Wing UAV SAR Project.
 

jross

Active member
#10
I've been thinking about something like this as a challenge. I'm a greenhorn but my first thought when reading your first post was that you need two different planes. A smaller plane with more range or time in the air and less payload (less expensive) and then the "big daddy" for heavy payloads. One would be a recon plane and the other used to drop payloads like radios, beacons, water, food or medical supplies. No sense sending a bomber on a recon mission.

In terms of planes and takeoff/landing zones you describe, it sounds like a belly lander would give you the most flexibility if combined with a catapult or bungee launcher. Of course that would eliminate mounting a $7000 FLIR on the bottom of the plane or at least make it difficult.
Another thought was why not put the motors on the fuselage in a push/pull design. Having 4 motors and all associated connections to disconnect/reconnect with the wing every time it flies creates added complexity, chances for mistakes and time. I'm no electronics genius but having 4 motors seems more complicated than necessary. The C130 is a flying brick and with power to weight ratios being much higher on a scale plane, there must be a two motor setup that could accommodate your payloads etc. I would strive for simplicity of build and setup.

I worked SAR long before all the new fangled equipment. I spend a lot of time in the bush, summer and winter. As I was ski touring on Saturday, I thought about what it would take to get a scale plane with payload to where I was skiing. If I'm in the subalpine, I'd be easier to find. In dense or mature timber, a full scale aircraft would struggle to find me and a scale aircraft would be no different. I stood under a tree and looked to see site lines from the air to my location. Imaging directly downwards wouldn't find me. The camera would have to be facing somewhat sideways and require multiple, different passes to find that window between me and the sky. Add to that the location I was skiing would be at the extent of a plane with a 30 minute flight time and not allow for loitering. To be effective with a 30 minute flight time, the plane would have to be snowmobiled much closer to my location prior to launch. If I got lost or injured, mustering where I left my truck would be all but useless. You'd need to start where I left my snowmobile at the end of the road. Which brings up another question. How do you make this thing portable enough to fit on a snowmobile or quad? A big, fancy ground station in a trailer is nice but in this situation would be useless so a portable ground station would be essential. Practicalities that need to be considered before you pick or design a plane.

A cool project though.
 
#11
I've been thinking about something like this as a challenge. I'm a greenhorn but my first thought when reading your first post was that you need two different planes. A smaller plane with more range or time in the air and less payload (less expensive) and then the "big daddy" for heavy payloads. One would be a recon plane and the other used to drop payloads like radios, beacons, water, food or medical supplies. No sense sending a bomber on a recon mission.

In terms of planes and takeoff/landing zones you describe, it sounds like a belly lander would give you the most flexibility if combined with a catapult or bungee launcher. Of course that would eliminate mounting a $7000 FLIR on the bottom of the plane or at least make it difficult.
Another thought was why not put the motors on the fuselage in a push/pull design. Having 4 motors and all associated connections to disconnect/reconnect with the wing every time it flies creates added complexity, chances for mistakes and time. I'm no electronics genius but having 4 motors seems more complicated than necessary. The C130 is a flying brick and with power to weight ratios being much higher on a scale plane, there must be a two motor setup that could accommodate your payloads etc. I would strive for simplicity of build and setup.

I worked SAR long before all the new fangled equipment. I spend a lot of time in the bush, summer and winter. As I was ski touring on Saturday, I thought about what it would take to get a scale plane with payload to where I was skiing. If I'm in the subalpine, I'd be easier to find. In dense or mature timber, a full scale aircraft would struggle to find me and a scale aircraft would be no different. I stood under a tree and looked to see site lines from the air to my location. Imaging directly downwards wouldn't find me. The camera would have to be facing somewhat sideways and require multiple, different passes to find that window between me and the sky. Add to that the location I was skiing would be at the extent of a plane with a 30 minute flight time and not allow for loitering. To be effective with a 30 minute flight time, the plane would have to be snowmobiled much closer to my location prior to launch. If I got lost or injured, mustering where I left my truck would be all but useless. You'd need to start where I left my snowmobile at the end of the road. Which brings up another question. How do you make this thing portable enough to fit on a snowmobile or quad? A big, fancy ground station in a trailer is nice but in this situation would be useless so a portable ground station would be essential. Practicalities that need to be considered before you pick or design a plane.

A cool project though.
Two planes... Two Planes... TWO PLANES! By jove, I think he's got it! You made one heck of a point about portability for the ground station. One of the best ones I've seen is built onto a heavy duty hand-truck of all things, swing open Pelican case that everything folds out into a system. Choosing a Recon aircraft backed up by a cargo planes sounds like the best move. Quick set up sectional aircraft for recon have been around for a decade or so for military and government use. Suggestions for a possible FT Kit as a recon plane at this point would be greatly appreciated. Single engine easy to fly, study bird, space for cameras, FPV capable. The Cargo plane could then be a Herc based, or even a SC-7 Skyvan. Or just a slightly modified Guinea Pig! PaintPatternN181GP02.png
 

CrashRecovery

I'm a care bear...Really?
Mentor
#12
Discussing this with a few other rc geeks I know your problem is going to the cube loading. I'm going to copy one part of the conversation we had....
" Cube loading. Some rough numbers... used full scale C130 as basis for wing area at 60"... If the plane was weightless the cube loading would be 10.8, similar to a sport model. Even if he packed everything in to a 5lb plane his cube loading is getting up to around 20. That's up well into jet territory. Going to need a really beefy power system to maintain those speeds."
 

b-29er

Active member
#13
1) Field Conditions. As mentioned in 3 d / This will be variable, from pavement, gravel, grass, cut straw, snow. Anything i can land on with a 3" foam wheel or equivalent. Possibly general belly landing if needed.
2. Flight time. Normal SAR flight ops require flight to search zone, then a "Mow The Lawn" pattern flight watching and recording down view cameras. Once that grid is cleared, either move onto the next, or return for battery pack exchange, fly to next grid. Since requirements carry many variables on flight time, I will consult those in the know about balancing weight, power and equipment. Most aircraft are built and fly with a 15 minute flight time. I hope to increase this to a minimum 30 minute foul weather time, if not more.
3. In creating this system I looked for the best full sized design used in such SAR, heavy haul, long range, bad weather handling aircraft. Almost every such bird is 4 engine, or at least a Turbo-Prop Twin. Because of the high possibility of rough runway conditions, Overhead Wing Design and Multi-Engines uses smaller props mounted on the high wing avoiding ground FOD (Foreign Object Damage). And the size of my bird is also important. Even though it will be built portable by sectioning, anything much over a 5'/60"/1524 mm wingspan will take up to much room at SAR Command, or near there. Finding room to set up a Field Expedient Runway and being able to maintain it during SAR operations is also a key factor. Therefore...
4. The Cargo Bay is planned to be 5"/127 mm tall, 7"/177.8 mm wide, 24"/609.6 mm long. This does not include Cockpit/Nose or Tail/Rudder/Elevator section beyond rear cargo door. Plans are for the flat (mostly flat) tail area to extend forward to just behind the cockpit/nose. With this cross section, there will be ample room for avionics, power, camera systems. Avionics can by design be assigned space in the central wing area to include possible range extension secondary receiver near or in the tail section.
5. Having chatted with a couple of SAR personnel, the ESP's (Emergency Supply Packs) will be set up to be approximately the size of a 2 liter bottle or less, for the First Response Packs. The main objects will be a beacon/radio, batteries for extended operation of at least one cycle longer, small water bottle, possibly a first aid kit. The FR-ESP's will not necessarily be universal, but exchangeable to meet local conditions at the time and location of search. Follow up ESP's with specific equipment to meet on site requirements for victims and searchers are planned, as first stated.
Bomb Bay: This idea banged around, but was negated by the need for a solid fuselage floor for camera operations, and structural simplicity. In case of main landing gear problems/rough terrain issues, belly landing with bomb bay doors would mean a high level chance of serious damage to the aircraft. Support structure for such a system would also increase weight. I have also considered negating the cargo door, opting for using two servos to control the cargo release system, instead of one for the door, and one release. This will largely play out in the final aerodynamics of the plane, if removing the cargo door altogether will create to much drag, lowering flight time.
I hope this answers your questions. Please ask more if you feel I haven't answered these or you have further questions. I appreciate such thought provoking, so that I don't become narrow of focus on this project.
Ok, so if you are looking to deploy this on a variety of terrains, i think you are either looking for fixed landing gear or a belly lander with retractable camera bay. JROSS has a very valid point of making this thing bungee launchable, since that reduces the risks of hand launching and requires less space so my next question is what is the budget? You're looking at several thousand dollars in a payload, and the point of putting that on a DFTB airplane is about the same as putting a real diamond on a paper ring, unless theres a point, like you want this to be buildable from materials readily accessible.
As for your multi-engine experience, theres something to remember about the c-130 and that is its size. The engines used are very high on the list of power ratings, like #4 and #6, depending on the engine. There are plenty of motor choices out there that can easily run this aircraft on one or two engines without a hitch. The C-130 wasn't designed around its SAR role, either, it was designed for transport, but the requirements for this also make it good for all-weather SAR. I'd argue some of the single engine drones out there, like the Reaper SUAS or Globalhawk would be better SAR platforms (if you weren't dropping hellfires from the Reaper) due to the extreme time on station, because they are designed around a long-range, long endurance reconnasance role. I understand your emphasis on all weather flight, but i probably wouldn't put all-weather and foamboard in the same sentence without some extreme TLC.

On your cargo release, i would probably argue you may do more harm than good having a rear hatch primarily for complexity of release and potential CG issues. To release something out of a rear hatch, you need to either have a drogue parachute to pull your equipment out, or you need to put the aircraft into a steep climb. If for whatever reason your aircraft fails to release but the cargo shifts position, you wind up with an aircraft with an aft CG. An alternative would be to have a side-based drop, i.e. have your payload slip out of the left or right side of the aircraft. That way, you can have a precision drop by putting the payload on a ramp or a retractable point on the side of the aircraft, and no risk if your payload fails to deploy. Though the simple solution would be a single bomb bay, and if you have a square fuselage, use two skids that protrude 1-2 inches down below the bomb bay for landings.

Just a thought, but wouldn't having two aircraft introduce delay? i.e. you need a second pilot, or you need to land one aircraft, take off with the second, return to where you were to drop?

One final thought, how about a loudspeaker? Rather than having someone look for a quiet electric drone, why not have a speaker on the aircraft that either replays a message or is connected to a handheld radio for the pilot to relay instructions?
 
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Headbang

Well-known member
#14
My quick thoughts and seconds.

1. Not sure 60" wing in a conventional design will handle the payload (pretty sure it would not really), and have any reasonable flight time. Think 80 to 90 inches with a 16lb all up weight including payload, this allows a weight budget for higher capacity batteries, payload, electronics.

2. Dtfb does not last long, even water resistant starts to delaminate after not too long. Cut foam or formed foam, or even depron would be better for this. I would make sectional templates and cut foam. OR a low cost ready to fly foam plane, and modify it may be better, cheaper, more reliable.

3. 4 engines adds 4 times more things to go wrong. Anything used in emergency services need to be kept as simple as possible for field repairs and general reliability.

And probly a hundred other things I did not mention or have not thought of.
 

Userofmuchtape&glue

Posted a thousand or more times
#15
Yes, 4 motors does not really make sense to me. Full size planes use 4 motors because of power constraints and the need to use engines that already exist to keep costs down but with a model, it would make more sense to use 2, larger motors as this would cut down on wiring as @Headbang mentioned, while increasing reliability and efficiency. It is more efficient to use less motors producing more thrust if you are looking for maximum flight time.
Another thing I would recommend is a high voltage set up. More volts equals more efficiency so maybe looking into some large drone motors that run on 6S would be a option.
 

b-29er

Active member
#16
Yes, 4 motors does not really make sense to me. Full size planes use 4 motors because of power constraints and the need to use engines that already exist to keep costs down but with a model, it would make more sense to use 2, larger motors as this would cut down on wiring as @Headbang mentioned, while increasing reliability and efficiency. It is more efficient to use less motors producing more thrust if you are looking for maximum flight time.
Another thing I would recommend is a high voltage set up. More volts equals more efficiency so maybe looking into some large drone motors that run on 6S would be a option.
Higher voltage also means lower amperage. Lower amperage means lower gauge wires to distribute power. And lower gauge wires weigh less.
 

jross

Active member
#17
One final thought, how about a loudspeaker? Rather than having someone look for a quiet electric drone, why not have a speaker on the aircraft that either replays a message or is connected to a handheld radio for the pilot to relay instructions?
Good point. Sound could draw someone into a visible position who was hunkered down somewhere staying warm and dry. Someone lost or injured won't likely be looking for a plane so you'd need to draw their attention for sure. My suggestion would be to use a siren sound like a battery alarm but louder. You want a sound that will penetrate and a human voice isn't terribly good for that. Why most knowledgeable people in the backcountry carry a good whistle. A good whistle will carry for miles. After you have established visual contact, switch to a speaker and human voice to provide comfort, direction and inform. Using voice from a moving plane would be complicated too. Spit out half a sentence, turn around and fly back to finish the sentence. It could take a while too communicate much. That's where the ability to drop a small radio reliably would be huge.
 

Userofmuchtape&glue

Posted a thousand or more times
#18
@jross all good points, but with a aircraft like this that would have a maximum range of 15 kilometres (estimate I have no idea) how many lost people would there be in that radius? Of course you could drive out to a mountain top and establish a base of operations from there, and I don't know the mission parameters but you would need to carefully consider how much weight a speaker and radio is going to add to your AUFW.

Again, I'm just rambling so take me with a grain of salt :ROFLMAO:

What is the actual goal of this aircraft? The OP"s where not very clear...
 
#19
Hmm. One message/step at a time, so here goes.
1. @CrashRecovery Wing loading: Cargo Plane change to something closer to a SC-7/C-23 Short Bros. Skyvan. Actual plane is Twin Turbo-prop, high load wing-big square box fuselage-twin tail-cargo monster. Mainly now used as parachutist plane and... (Deep Breathe) Heavy Lifter into smaller airports. The Bird regularly can haul small cars close to it's own weight!
2. @b-29er DTFB is my first QUICK choice for the construction of the plane due to Availability/Price/Ease of build. I.E. Tough stable cheap platform to use to get equipment into the air and to the job. Backup plane parts can be on hand to strip from a sagging/damaged bird straight into a fresh one in minutes. But I have also thought ahead on material point. Something I want to try that is weight equivalent/but much tougher... Corrugated Plastic Sheet. Comes in many BRIGHT COLORS/Printable/Paint able/Tough. Downside is construction is Plastic Welding or Rivets. That forces some unique chances to plans, but hopefully with much thought not to hard to calculate. Polypropylene co-polymer resin is Milk Jug plastic. Can't glue it because that's what the Glue Bottles are made of! Go figure.
HEAVY EQUIPMENT DROP (HED pronounced HEAD). Drone chute palatalized loads have been nose up slide/pulled out of cargo planes from as far back as WWII. On YouTube people using FT Guinea Pigs are dropping FULL 2 liters with a small drone chute all the time. Should be a National RC Cargo Drop Competition. Get a 6 ft/1.9 meter vinyl target circle to stake on the ground, pick a day, pack plane/batteries/2 liters filled with water with chutes/guts and patience... FUN!
Twin Engine covered above. Sound? Hang on.
Two Planes: 3 person flight crew. Cargo Plane on ground/launch ready while Recon craft in air. Once found one of the crew (Pilot qualified, most likely visual spotter) takes off to drop supplies. This is a straight to site flight, not as long as Recon, GPS and Recon overwatch guided, determining best drop zone location. Army/Air Force has been using such systems since WWII for bombing/resupply. Think Broncos and Herc's/C-5 A's/B-52's. Option.
@Headbang Thanks for your input. Hope I'm covering this stuff.
@Userofmuchtape&glue Dude! Higher Voltage! 6S. Hmm. Will look into this. Simplifying to a twin engine set up can remove Power Hub, but may have to look into using a higher voltage unit.
@jross Siren Whistles. Idea of making my birds sound like a Turbo-Prop plane led me to pick up cheaply a ton of those silly Siren Whistles we used to play with as kids. I have one mounted under each power pack on my Scratch Built Guinea Pig/Skyvan for testing. Guarantee THAT WILL BE HEARD! So far trials are good. Will have to post short video here. Again guys, Small Beacon/Radio is #1 on ESP drop list.
Great session of Q and A. Hope I can include/hash out every design aspect and begin to lock down parameters sooner than later. Just in case someone thought of this already, Recon Plane could possibly be operated by another crew/or be a quad. I'm thinking a quad may have a shorter flight time for long slow pattern searching requirements. We'll see.
Thanks again for all your input. Happy Flying! 275605.jpg
Note car in cargo hold! LOL