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How Far Can a Spear Go?

synjin

Active member
#1
So, I was out flying the FT Spear today (that's always a fun fly!), and with a 3S 1800maH battery it stayed up for 15 minutes and came down with 21% left on the battery. So, I was wondering how far out I could fly with a Crossfire TX and RX and FPV set-up? I guess I'd have to use a flight controller board with the Crossfire.

There's a mountain top about 2 miles away and about 1300 feet up from the back of the house. That would be a cool GoPro flight.

Will the Spear do that, or is there a better wing to build for that?...(like a 250% Dart)

Just wondering where the limits are.
 

ElectriSean

Eternal Student
Mentor
#2
Your biggest limitation will be the FPV system, though 2 miles can be done with a decent directional antenna on the Rx. A bigger battery wouldn't hurt, always good to have more than you need. I wouldn't do anything long range without a FC and GPS for a RTH failsafe.
 

synjin

Active member
#3
Well, I was going to try a 2800 3S tomorrow and see how long it will stay up. If I can get it to balance, I'll also try a 3600 3S. I thought I'd work my time up and then go for distance. At the very least I need battery voltage telemetry. Yes, eventually, if I go forward with this, I'll need the FC with RTH.

To be clear, I intend to stay within 400' of the ground, it's just that the ground will be tilting up considerably.
 

moret

Well-known member
#4
To be clear, I intend to stay within 400' of the ground, it's just that the ground will be tilting up considerably.
I sure if you are FPV you don't want to hear this, but the FAA also says that you must have a spotter and they must be able to see the plane at all times.
 

FDS

Well-known member
#7
They can do long range in some places with agreements. Otherwise they are simply flying illegally.
You don’t need a FC with Crossfire but it does help with things like GPS return etc which are useful if you are beyond LOS. Look at the Matek F405 wing.
21% is a sensible margin in your battery. You don’t want to be trying to land with less than 3.6v per cell constant voltage. If the battery gets lower it falls off a cliff output wise, this happens fast and usually means a crash or at best a puffed lipo.
I would drive nearer the mountain and fly it, save the energy of the boring return flight. Remember all those new laws are just waiting for someone to be used on. Fly safe first.
 

Merv

Well-known member
#8
I live in the corn belt, it's an ocean of corn, it's easy to not know which way home is. I learned the hard way not to fly without someway to point home.

Here is the first of several in the series for a cheap fix. GPS without a FC.

 

synjin

Active member
#9
They can do long range in some places with agreements. Otherwise they are simply flying illegally.
You don’t need a FC with Crossfire but it does help with things like GPS return etc which are useful if you are beyond LOS. Look at the Matek F405 wing.
21% is a sensible margin in your battery. You don’t want to be trying to land with less than 3.6v per cell constant voltage. If the battery gets lower it falls off a cliff output wise, this happens fast and usually means a crash or at best a puffed lipo.
I would drive nearer the mountain and fly it, save the energy of the boring return flight. Remember all those new laws are just waiting for someone to be used on. Fly safe first.
Driving nearer the mountain isn't going to change things much, as it would save about two blocks...maybe three. After that, it's 200 miles to the next town in that direction over mountains and glaciers.

It's not like my goal is to flout laws (as imperfect as I think they are), it's really the challenge of the thing, especially if it's with a foam board airframe. I can probably do the same thing with the 9" quad frame I'm finishing up on the project table, but part of the entertainment factor is the fact that I can try something like this with foam, foam board and hot glue.
 

Attachments

#10
Hey dude,

I've converted my scratch FT spear mainly installing 5000mah 4s2p Li-Ion battery, Otherwise it flies with Radiolink MiniPix- Arduplane, Dragonlink V3 with telemetry 1W and gopro Hero 5 Black. I dont use FPV, because it feels too much hustle, I fly on telemetry when out of sight, or mostly doing missions. For flight times it flies around 50-60 minutes and covers around 50-60 km cruising.

Total weight (AUW) is 1160g.
Last mission I tested was 34 km and I flew like 20 minutes after that lowering my altitude gradually.

I've put all batteries in the back on both sides of the thrust section in order to balance the GorPro. Motor is NTM PropDrive V2 1200 with 30A ESC, 8x4.7 or 8x6 APC.

FT Spear is super capable platform, it's smooth.

Best,
 

synjin

Active member
#11
Well, I need to build a new one, as I bounced my Spear off the ground one too many times. The new one will have FVP and camera mounts from the start.
 
#12
Good luck with the new build man, make it double strong, add autopilot, rtl and stabilization, you won't crash that much.
I don't see any more capable design out there.

Best,
 

sprzout

Knower of useless information
Mentor
#13
Wife with binoculars.
Hate be the bearer of bad news, but binoculars aren’t legal for use by a spotter, per Advisory Circular 91-57B :

Visual observers need to be co-located with the recreational flyer, and able to communicate directly with the recreational flyer without the use of technological assistance.

The above translates to no walkie-talkies, cell phones, spotting scopes, etc. Gotta use the ol’ Mark I eyeball.
 
#14
Hi,

Just uploaded last week mission to YouTube (Sakar RC channel). Flight was 38 km total distance, 23 km mission, 11 km farthest point from the station, on landing it had at least 15 more minutes flight time.
If you watch careful you can see spotters every 100m, shouting at each other when the plane passes. It was fun organising 250 people doing that.

Hope you enjoy the view and get the idea of capability of FT Spear.

Best,