Is there realy a difference between 9443 and 9450 props?

[Gerard Nijenbrinks]

Due to a Facebook DJI Phantom group posting I had a look at my props (Phantom 2 V2 & H3-3D).

Out of the box 9450's were fitted, and another set of them were added in the box separately. As an incentive from my (official DJI) dealer I got an extra set of props (an extra battery and a camouflage sticker set).

I have changed the props which were fitted out of the box with those given by my dealer, because I wanted to see if there was less vibration with the other set (there was slightly).

Now I found out that the extra given set are 9443's. Except for probably a little less vibration, I have not mentioned any other behavior of my Phantom 2 however.

Are we sure that there are really important differences between the 9443 and 9450 props?

 

[lake_flyer]

Hallo Gerard, welcome fellow countryman.

To answer your question you should first know that DJI had a problem with the 9443's because many people reported that they encountered VRS or Vortex Ring State, during descend, causing a lot of crashes. DJI immediately limited the descend rate in the firmware for the entire P2 (V+)model line. They even implemented an auto descend mode that's invoked whenever you keep the throttle stick down for a couple of seconds (which I find extremely stupid and annoying). At the same time they developed a slightly different prop, called the 9450, that's supposed to overcome these problems. They provide a little more thrust so they theoretically could provide a few more minutes of flying time or a slightly heavvier payload. That said, DJI didn't lift the descend restrictions so we are all still stuck with 2m/s descend with which both props so it doesn't matter much anyhow..

The only users who really can enjoy the features of the 9450's are P1 and FC40 pilots with NAZA-M. They can hurl down at any speed and because a lot of them use the 9443's for extra lift and flying time (stock props on those are 8"), they are the first to encounter problems with VRS. So for them it could be a godsent if they can just fly without VRS worries. I haven't tried them on my FC40 yet but I will soon.

I would use the 9445's just to stay on the safe side.

Cheers
Jan

 

[Gerard Nijenbrinks]

Thank you very much for your swift and substantial reply Jan,

I'm a careful flyer still, so that's probably why I didn't experience VRS problems with my 9443's yet ;-)

I found a comparing video on YT between the 9443 and 9450 props as well by the way. In this video https://www.youtube.com/watch?v=8gBX8NNPtvs there's a battery-life test at 14:25 where it looks like the 9450 props give considerably less battery life than the 9443s, opposite to you assumption that they could provide more minutes of flying time.

More trust could mean more power consumption as well probably...

Thanks again and best regards,

Gerard

 

[Gerard Nijenbrinks]

Sorry, forgot to ask..

You mentioned: "They even implemented an auto descend mode that's invoked whenever you keep the throttle stick down for a couple of seconds"

If I'm not mistaken, if I'm keeping my throttle stick totally down for a few seconds (it even sticks there automatically) my motors shut off entirely. That to me seems a quite drastic auto-descend mode, and not one should want to use I've read about other people finding it rather stupid and annoying as well.

I didn't want to try it during flight though; is this 'shutting-off motors' function probably not available in flight? I would hope so...

G.

 

[N017RW]

Looking at the numbers the 9450's have more pitch.

The general rule of prop specing is the first # is the diameter of the arc, 9.4 inches, which they are, and the second # is the pitch 4.3 and 5.0 inches respectively.

Thus the 9450s produce more thrust per RPM.

 

[syotr]

I have both. It seems to me that the 9443's give the longest flight time but the 9450's have more thrust and would be preferred on a heavily loaded bird.
Either will give more flight time than the original 8" props and will be less noisy but they are more affected by wind.

 

[msinger]

The only difference I noticed is that the 9450 props are quieter. The difference in flight time was not noticeable to me.

 

[Fplvert]

The only difference I noticed is that the 9450 props are quieter. The difference in flight time was not noticeable to me.

+1
If your props aren't balanced they can cause poor video (jello) and eventually crack the motor mounts. Love the 9450s BTW.

 

[msinger]

If your props aren't balanced they can cause poor video (jello) and eventually crack the motor mounts.

Good point. I balanced my props with the SpeedyTM prop balancer.

It's simple to do. Just had some clear Scotch tape to the light side of the props.

 

[J.James]

When I first got a set of the 9450s I could not see any thing that seemed to look any different about them from the 9443s

Tho i did notice right off the bat that they were a bit stiffer then the stock ones. and they seem to fly a hell of a lot better.

But even when I took out my micrometer the only thing that seemed to be different was they were a super tiny bit different at the spot near were the blade goes in to the hub and they are thicker. and it seems the top is whats thicker so it might be that they are getting more life from the tops being thicker causing more of a wing effect then the 9443s do.

 

[Meta4]

They even implemented an auto descend mode that's invoked whenever you keep the throttle stick down for a couple of seconds

There is no "auto descend mode" but the latest "upgraded" Tx has a throttle lock.

If I'm not mistaken, if I'm keeping my throttle stick totally down for a few seconds (it even sticks there automatically) my motors shut off entirely. That to me seems a quite drastic auto-descend mode, and not one should want to use I've read about other people finding it rather stupid and annoying as well.

I didn't want to try it during flight though; is this 'shutting-off motors' function probably not available in flight?

The throttle lock might be "rather stupid and annoying" but holding the throttle down will only shut off the motors after landing - not in flight. That can only happen after landing. DJI designers aren't that stupid.

 

[lake_flyer]

There is no "auto descend mode" but the latest "upgraded" Tx has a throttle lock.

You're wrong, sorry.
Hold down the throttle stick for 3 seconds and it stops forward motion, starts to descend automatically, even changes the descend speed from 2m/s down to 0.6m/s close to the ground and shuts off the motors once landed (you have to keep the throttle down for this, and that's why they came up with a throttle lock for the new Tx).

 

[lake_flyer]

(1) If you choose the Intelligent mode, and the throttle stick is under 10%, this will trigger the landing Procedure, in any control mode. In this judgment, pitch, roll and yaw controls are denied except the throttle, but multi-rotor will still auto level.

Found this in the NAZA-M 1.26 manual. It seems that it is a standard feature. But with a P1 or FC40 you are not tempted at all to hold the throttle all the way down while flying forward because it will come down like a rocket. The P2 (V+) will not go faster than 2m/s so I tend to increase the tension on my left thump to get as close to the max descend speed as possible and THEN it goes into landing procedure.

Got it. The 2m/s limit is the main problem, not the landing mode, because it's not a problem om the P1/FC40. I'm not going to mess with the Intelligent/Immediate Throttle response mode. I leave it on default setting.

 

[lake_flyer]

Thank you very much for your swift and substantial reply Jan,

I'm a careful flyer still, so that's probably why I didn't experience VRS problems with my 9443's yet ;-)

I found a comparing video on YT between the 9443 and 9450 props as well by the way. In this video https://www.youtube.com/watch?v=8gBX8NNPtvs there's a battery-life test at 14:25 where it looks like the 9450 props give considerably less battery life than the 9443s, opposite to you assumption that they could provide more minutes of flying time.

More trust could mean more power consumption as well probably...

Thanks again and best regards,

Gerard

Gerard, because of the descend limit to 2m/s you don't have to be overly afraid for VRS with the 9443's. It can happen but only when some things happen at the same time, like getting in a down draft while descending. But with 2m/s the reaction is very moderate, it will only drop a few feet (very quickly though) and stabilise again. I've tried to get VRS deliberately and succeeded to get it out of VRS just by releasing the throttle stick. With a faster descend speed things go south (down I mean) very quickly and almost anything you do will make it worse, except slowly easing the throttle to midpoint. Flying in a glide slope while descending is safer because you stay out of the turbulence of the rotors.

 

[Woods]

Thank you very much for your swift and substantial reply Jan,

I'm a careful flyer still, so that's probably why I didn't experience VRS problems with my 9443's yet ;-)

I found a comparing video on YT between the 9443 and 9450 props as well by the way. In this video https://www.youtube.com/watch?v=8gBX8NNPtvs there's a battery-life test at 14:25 where it looks like the 9450 props give considerably less battery life than the 9443s, opposite to you assumption that they could provide more minutes of flying time.

More trust could mean more power consumption as well probably...

Thanks again and best regards,

Gerard

Based on that video "battery life aside", I don't see the price difference being worth going with aftermarket for props.

 

[Gerard Nijenbrinks]

Thank you all for the informative responses. Going to change my 9443's back to 9450's now... ;-)