AS350 B3e Nr400 increase with cargo swing

[ktmnomad]

Hey, 

The last month I've been flying cargo on the longline non stop with a B3e fitted with the Airbus cargo swing and weigh system. When the VEMD detects a load on the hook it automatically increases the Nr to 400. 

It turns out we were borrowing the airbus swing system from another company and now we are getting the onboard system installed which doesn't have this Nr increase feature (Onboard are in the process of developing the VEMD connection to get this increase)  

I'll find out soon enough but I thought I would ask if anyone has experienced the difference in performance from the standard 394 Nr to the 400 Nr?

Thanks in advance. 

(photo shows Nr 400 not 477 lol) 

 

[ray]

On the B3e, there is a collective and pedal pitch position indicator that will increase the Nr to 400 if it measures a higher than normal movement on the controls. It is a variable Nr system. It will reduce the Nr if it measures low collective/pedal movement. I wasn't aware the cargo hook load cell does the same thing.

[ktmnomad]

Hey Ray, I realise the system is variable Nr but in my previous experience I believe it only increased to a maximum of ~394 while using the onboard system that doesn't talk to the computer or with full load in cabin (as needed). That was in the summer however and now I'm flying in totally different circumstances and altitudes where it would be impossible for me to compare what I was doing in the summer to where I am now with weight and performance. 

Yeah as soon as the computer detects a load on the hook, it just bumps up the rpm to 400, but only on the airbus system for now. 

[Heli500]

I belive with the onboard hook you will no longer be able to reach the max potential of the B3e as stated in the flight manual. This was Airbus fix  for the problem. You are going to have a tough time finding anyone with experience with the post mod airframe and siren hook, I think its very rare. Most opt for delivery with an onbard hook. 

It would have been alot better if you just could flick a switch and have the vemd/decu let the Nr go to  400 rather than have to detect a load.

Here is something to debate and maybe help you get your answer.

Will a straight B3 (2b or 2b1) out lift a B3e (2d & dual hyd)? In my head the lighter old B3 that does not have a governed down Nr should.

[Bee3]

The old 2b B3s with the light airframe will out lift the newer ones in my experience. 

[ktmnomad]

Ah okay, thanks for the further information.

I think it will be hard to find specific information about the performance increase with Nr especially in Canada as this is the first as350 I have flown with an actual airbus swing and weigh system. Our B3e also has the newest VEMD so I'm not sure if older B3e's even have this Nr increase capability to 400? 

You can tell the airbus swing because the whole swing assembly is at an angle unlike the dart and onboard swings. (it looks totally wrong and i questioned the install a few timesl, was assured it was correct lol) 

To clarify, its not the hook that matters, rather the weigh system which connects to VEMD that makes the Nr increase with load. Our actual hook with the airbus swing and weigh system is an onboard hook. (or the one we were borrowing) 

The answer about the Nr increase with onboard was answered by Onboard. I was more curious about actual performance gains with the higher Nr. I'l be back to long lining tomorrow as we just finished the install of the full onboard system (Weigh system, swing and hook). Will find out what i can or cannot lift as I'll be doing the same route as prior with the airbus system. 

As for B3e vs B3. Our B3e is a 2018 model with single hydraulics and empty weight of 2861 Lbs. We can't utilise the benefits of DH (5225 internal) so we save weight there. 

Pics 

(Swing set up, Hook and weigh meter showing KG)

From Onboard 

"Right now, only the Airbus factory supplied weighing system can connect with the VEMD. The C-39 indicator in all of Onboard’s STC’s will not work with the latest VEMD. We are designing a new indicator, the C-40 which will be able to connect to the VEMD and display weight and increase Nr when carrying load.

We expect the C-40 to be certified by HeliExpo next year – March 2019. We are waiting for some final information from Airbus in France in order to connect the C-40 to the VEMD"

 

[Heli500]

We were excited when this SB came out and wanted it for our B3e, that excitement faded fast when we realized it would not work with an onboard load cell.

You are in a unique situation were you can test the 2 versions. Would you be able to conduct an experiment where you load up a hook to max that your TQ limits and weight limits will allow. Try and lift it with the load cell conector disconnected at the hook. Then try it with it connected. See if there is a difference and if you can get the Nr to bump up.

 

It would definitely help some operators make a decisions on retro fitting older aircraft.

 

Why did they just not make a Nr trim switch. Then it could have been utilized with internal loads too.

[ktmnomad]

Hey Heli500, 

 I should be able to get a good idea of the change since I'll mostly be doing the same route with same approximate sling weight and the same fuel weight every flight. (refuel every load) 

At the destination for the loads, I am right on the limit to what I can carry as I am NG'ing out rather then TQ out so I won't be able to demonstrate max loads as far as TQ goes. (My TQ is 62% with FLI at 9 in forward flight)

Previously I'm taking off with 220 lbs fuel and 1550 - 1660 lbs of load at ~9560 ft. I'm not pulling max as I'm taking the loads higher but I'm usually at ~9.8 ish on the FLI and when I'm landing i'm at 10 for sure. Once the temps rise a few degrees, the load goes where ever it is that my air speed slows to zero or before (of course i'm timing that spot for the two 2 x 4's laying on the ground) and then its not moving from the ground...

The whole airbus system was ripped out the last days and now we have the complete onboard system so I won't be able to just disconnect or reconnect anything as that system is history. However, in march next year, I'm sure our company will get their hands on that Onboard C-40 connector which will enable the onboard weigh system to connect to the VEMD and therefor bump the Nr up to 400. 

A switch would be good for sure, maybe they thought people would abuse it or who knows... 

[ray]

I see what you mean about the cargo swing. It looks like the frame is installed backwards, doesn't it.

[ktmnomad]

51 minutes ago, ray said:

I see what you mean about the cargo swing. It looks like the frame is installed backwards, doesn't it.

It sure does! The angle you see in the photo is how it sits, the bungee cords are at the front and they really aren't doing much since the frame can't really move to the back anyway (it can but not like the on-board). The onboard one as we know, the bungees hold it back while no load, not the case here, this is how it looks with or with out load. I even messaged engineers from previous company and they said it looks wrong as well. 

However, the engineers here assured me it is correct and after looking at other helicopters with the airbus swing, they look the same.