Sometimes less is actually more - Avis 5 build

1. Intro

I've been few years into the hobby, most of my freestyle builds are around 360-380 gr. dry (no gopro no battery); seeing setup specs and parts list of top pilots the ~550 gr AUW weight mark is the holy grail of freestyle builds, after flying this setup I can easily agree and understand why ?

1. Flight time is around 5 min, using 4S 1300mAh Thunderpower Lipo and Session 5 onboard.
2. Propwash handling is superb, prop loading makes a huge difference here. (Prop loading - amount of weight each prop needs to handle)
3. Response times with HQ 5x4.3x3 V1S are exccelent, the weight plays big role here, the lower the weight less stress is put on the battery when motors need to accelerate.
4. Flight dynamics are excelent, it's possible to perform sharp manueveres yet there is just enough mass to make things handle steadily and feel locked in.

2. Frame

I've considered few options avaliable on the market...the most prominant being Bob Roogi (KababFPV), Floss Style frame...the single NO imo is the frame layout being a stretch X for freestyle, apart from that it's an amazing frame at an amazing price from an amazing and gifted designer... well done Bob.

I've decided to design my own frame to meet all my dreams and wishes (being mechanical engineer, I design stuff much more complicated on a daily basis).
I wanted well balanced frame with more or less similar response on the roll and pitch axis, with the batery and HD cam given - this dictates making the pitch short and roll axis long to balance moments of inertia, but props interaction limits how close props can be apart...I've settled on 144 mm MTM roll direction and 172 mm MTM pitch direction hence the frame is squashed X, amount of squash is less than in ImpulseRC Alien or Armattan Chameleon frames.
The frame is called Avis 5" (Avis - is a bird in latin)

Arms are 5 mm THK. chamfered all around and interlock at frame center, all other carbon parts are 2 mm THK, when assembled steel screws for the arms and Ti screws for the top / bottom plates, frame weight is just under 100gr. Bottom plate supports both 20x20 and 30.5x30.5 mm stack options, standoff height is 20 mm to maintain low CG, advanced builders may opt for 15 mm standoffs also shaving few extra gr.

3. Components choice and considerations

1. Motors - I've had a set of BH R5 laying around...if I had to buy today I would probably go with Tmotor F40pro V2 or MB Primo 2207 or Hobbywing Xrotor 2207.
2. FC + ESC - I love Airbot stuff I think he is #1 electronics designer out there, I went with Ori32 + F4 Nano V5 combo, the 25A ESC rating may concern some but from my testing such rig on HQ 5x4.3x3 V1S - should pull around 85-90 amps top hence 25 amps per ESC is more than enough... the only downside I can think of is the lack of onboard flash for BB analysis but I think that had been addressed in F4 Nano V5.1 version.
3. VTX & Cam - as always IRC Tramp HV - is my favourite VTX, powered via. FC LC filter and supplying 5v to the Runcam Micro Swift V1.
4. Reciever - TBS Cross micro with Immortal T on the arm...
5. Panasonic FM 1000 uF 25V cap connected to mains.
6. Matek buzzer - 3 wires buzzer, very loud and flat for easy mounting.
7. Soft mount for motors + FC, motors wires wrapping - blue nylon sleeve.
   

4. Build tips

1. Plan, plan, plan and then execute...I usually make connection scheme and dry place all comp. into their locations.
2. Soft mount motors, soft mount FC.
3. Thermal pad between Tramp can and frame bottom.
4. Do not allow anything loose near the FC - use zip ties or hot glue everything.
5. Take the time building, enjoy it and document - this will make the build last and in the event of something going wrong most chances you know where to look.

5. Some flight videos