Marc's Public Blog - Remote Control Aircraft

After trying the draganflyer Ti (thermal intelligence) for a few days, I ended up returning it.

It worked really well outside thanks to its thermal intelligence (it had 4 heat sensors that could make the unit self-level by seeking the temperature difference between the sky and the ground).
Unfortunately, without thermal intelligence, indoors, it just wouldn't level that well, which was disappointing for a $1000+ RC device, so I returned it.

You can find a few videos here , and if you are curious, the details of my experience are below (as the reason for return that I sent that company)

Below, I am going to give you details for the benefit of your design
team.
While I have obviously had it for more than 1 month, it was DOA and I only
received a working receiver board last week.
I tried it the next day, and the day after with help and feedback from your
tech support, but ultimately, I was disappointed with it because of its
performance when Ti was not enabled.
Your support folks reviewed test hovering videos in my house, showing how
wobbly the unit was and how hard to control it was. They suggested prop
wash, so I went to a bigger indoor facility and had similar results:
The DF does a bad job of saying level or in one spot without Ti.
I'm sorry, but a $150 X-Ufo does a near perfect job of this until you spill
its mechanical gyro. Whatever your solid state gyros do, is good enough to
run the motors in a way that the unit doesn't flip over or stays generally
level, but they can't keep the unit fully level and hovering without Ti.
The X-Ufo can, and with a solid state gyro upgrade kit from Germany, it does
apparently fine flying outside in winds (which the mechanical gyro can't
quite do).
As things stand right now, the DF Ti does do a great job flying outside with
Ti on, but it's just very disappointing without Ti. Because I typically
mostly fly indoors, it unfortunately makes the unit unsuitable for my use
and I would therefore like to return it after 2-3 days of use/testing.
As additional things that disappointed me and that you'll want to look
into fixing:
- a $1000+ unit shouldn't be using analog transmitters anymore. You should
  at least provide a Spectrum DX7 receiver board as an option. There is
  too much chance of RF interference risk in some of the places I fly in
  and the present is digital DSM2. Analog is dead.
- The new style remote you provide (with the Ti on/off switch) just feels
  cheap. Again, it's disappointing for an expensive device like this.  I
  found that it was very hard to give precise, timely, and small control
  inputs to fly the unit indoors: the remote is not proportional and doesn't
  provide enough precision for very small inputs and corrections
- Again, because you use a cheap remote with no intelligence, I have to trim
  it when flying without Ti, and then untrim/retrim it every single time
  I switch to and from Ti mode. That's just silly and hard to accept for
  a unit that price (and even more so for the multi thousand dollar units)
  Again, allowing for the customer to use his/her own DX7 transmitter by
  putting an AR6xxx receiver on an optional board, would fix this.
- your motor mounting rods should have a pinhole or square pattern that
  would allow for the motors to not spin around the axis and always point
  up. The premounted unit that you shipped me didn't even have the motors
  mounted right, and they were quite hard to adjust.
- Generally, the gyro input or feedback is poor. I know the solid state
  gyros work because the unit wouldn't fly at all without them, but even
  when perfectly trimmed, your unit does not self level indoors with no
  control input. The X-Ufo does.
- Your lipo charger seems slow compared to a real thunderpower charger. I
  have 3 cell lipos that look almost identical to yours, but your packs have
  the balancing connector removed, making it difficult to consider charging
  your batteries or using my own with a real lipo charger/balancer (BTW, I
  did not charge your batteries with anything else than your charger since I
  didn't know whether it was safe, but I also noticed how slow your charger
  was).
- your folding blades are hard to adjust so that they self straighten, and
  when they fold, they get caught into the motor gear and stop the motor,
  which can't be too good for it.
I still believe that your product is probably the best one around for flying
exclusively outside with Ti on, but due to the points above, and the fact
that I mostly do indoor flying, I'm going to go the X-Ufo with gyro upgrade
route.