Have I enough power?

[Ronos]

There are a couple of posts on here about the VQ Hurricane, believe me I have looked, but not much info. On one thread a SC70 + 500g of lead to get the CoG at 85mm. The thing is there is no battery hatch, you have to take the wing off the change the battery, i think personally it s designed for IC. I have the VQ FOCKE WULF 190 with a SC91FS up front and I had to put weight on the tail to get the CoG. I think with a 6s you would struggle to get it in with out some major alterations to the firewall and inner bulkhead, also the motor mount could cause a problem depending on the size of the 6s battery.

[PatMc]

Posted by Piers Bowlan on 30/01/2020 22:08:01:

I maybe now about to eat my words!

I see on the Hobby Plastics website that a Saito FA62B is the recommended IC engine for the VQ Hurricane, and this is claimed to produce .95 PS. That equates roughly to about 750 Watts. I also see that the model RTF weigh is 6.5lbs, so 800W - 900W should be enough as a ball park. So with a 4s battery at 14.8v, 60Amps should produce around 900W. The question is, what size of propeller will draw 60 Amps? Your 14 X 7 is only drawing 37Amps so it needs to be bigger.

The problem with using a 6s LiPo is that the weight and wing loading will increase. That doesn't solve the problem of the c of g. Have you found any VQ Hurricane electric conversions online? Could the c of g position be wrong and is moving the battery forward, beneath the motor, impossible? Adding 40oz of weight to the nose does not seem like a recipe for success.

A 6s lipo producing the same energy as a 4s will be no heavier. But the higher voltage enables the choice 50% more power for the same current, or the same power for 50% less current, or something in between.

[Richard Wills 2]

I have both the 46 and 60 VQ Hurricane, and I think the specs on the site are wrong, they match what the 46 acually weighs. The 60 came in at 10.5lb

My 60 has a 91 FS engine and 19oz of lead bolted onto the engine mount total of 43oz, but I have moved the cg back a little from the manual. The electric motor is 10oz so total of 50oz on the front, so not far out of what I have if you are on the marks.

I get 8300rpm on a 14x8 and to be honest it is marginal for power, no way it would fly on a 62 so that info is probably for the smaller one too. The pitch speed is fine, but needs more thrust so I would try 15x8 or 16x8 and see what numbers you get as you seem to have some head room.

It flies great but it is heavy so watch it. The stall when it comes is vicious so careful on that elevator, the manual throws at 10mm are generous.

Edited By Richard Wills 2 on 31/01/2020 05:32:57

Edited By Richard Wills 2 on 31/01/2020 05:37:06

[Low pass Pete]

Just been reading this whole Blog with interest. Also have looked at the Hobbyplastic site as well. They actually quote a Saito 82 not a 62. I have a Hangar 9 50in Corsair and that had a Saito 82 which was ok but now fly's better on an OS70.

Looking at the specs for the VQ Hurricane 60 I would personally put nothing less than a 91 4 stroke and think an OS95V or a Laser100 would be much the best choice of IC engines that are available to buy new today. Now way wouId a Saito 82 fly this model well. I have a H9 Thunderbolt 63in that has an OS 95V upfront and that is a good match. Richard's comments seem very informative and helpful.

Sorry I cannot help on electrics but as you probably gathered I'm not into electric so far and all this makes me think twice especially for a warbird.

Good Luck and best regards

Peter

[Ronos]

Nice bit of info lads, like I said I have the FW190 with the sc91fs up front but not had its maiden yet. I have a 15x8 there,just have to make a Y lead for the battery connection. Thanks for the heads up on the stall I have the Seagull mosquito which is really over weight but flies great and has the same stall characteristics as you describe. Busy day ahead .

[Nigel R]

I think you'll have more luck with the 6s setup. The 580kv type motor is not really aimed at 4s use, its a little too slow.

For some comparison my 4s setups use motors of about 900kv, and that puts them at about 10k rpm (or so) with a suitable prop load (as a side note those are all 20 and 40 size airframes).

You can use lower kv ratings - but have to go with a very large prop.

A higher kv rating would conversely need a very small prop.

I think Piers post is on the money:

"Hobbyking NTM 5050/580kv motor. He ran it on 6s (22v) and fitted a 15x7 propeller. It pulled 65A and produced 1443Watts. So the 14X7 prop you have been using may be perfect when used with a 6s LiPo. "

[Ronos]

So guys, I am looking at(roughly) something around the 60A mark and (roughly) something around the 1400Watts mark, and lets say starting off with a 15x8 prop, with a 6s.

[Dickw]

Posted by Ronos on 31/01/2020 09:38:34:

So guys, I am looking at(roughly) something around the 60A mark and (roughly) something around the 1400Watts mark, and lets say starting off with a 15x8 prop, with a 6s.

Yes, that woud be good, but not with your present motor - the kv is too high for that.

If you use your present motor on 6s the 14x7 would probably be OK, but I would start experimenting with a 13x6 to be on the safe side.

I have attached a data log from a 5055 motor on 6s with a 17x8 prop, but that was only a 400kV motor and it is still pulling near 60 amps.

Dick

Edited By Dickw on 31/01/2020 10:15:53

[Ronos]

Posted by Dickw on 31/01/2020 10:15:22:

Posted by Ronos on 31/01/2020 09:38:34:

So guys, I am looking at(roughly) something around the 60A mark and (roughly) something around the 1400Watts mark, and lets say starting off with a 15x8 prop, with a 6s.

Yes, that woud be good, but not with your present motor - the kv is too high for that.

If you use your present motor on 6s the 14x7 would probably be OK, but I would start experimenting with a 13x6 to be on the safe side.

I have attached a data log from a 5055 motor on 6s with a 17x8 prop, but that was only a 400kV motor and it is still pulling near 60 amps.

Dick

Edited By Dickw on 31/01/2020 10:15:53

Big thanks DickW. At least I have something to aim for.

[Bob Cotsford]

1000-1200W needed, 13*6 on 6S with that motor or get a 5055 430kv motor and run it on 6S with a 14*8 or 14*10 for extra oomph. A 63" warbird weighing 10lb or so is nothing new, the old TopFlite kits often ended up at that or more. 40oz of lead needed smacks of bad design but if it's what it needs, so be it.

My Bolero running a similar spec Power52 motor of 590kv takes over 60A for around 1300W on a 13*6.5 APC-E according to the logs, which incidentally is pretty close to E-calc's prediction for it.

 

Edited By Bob Cotsford on 31/01/2020 11:03:46

[Nigel R]

"40oz of lead needed smacks of bad design but if it's what it needs, so be it."

It sounds like an IC design that hasn't been modified for electric, going by the earlier post stating "wing off to change battery". I'm guessing the firewall is in the right place for a 90 four stroke, not an outrunner, and there's no scope to move the lipo forward beyond the tank bay.

Have to say, if it were me, I'd be getting the knife out and trying to get the lipo forward as much as possible and dumping some church roof. Maybe it could go vertical inside the cowl area behind the motor, or go forward under the motor, or something.

I note **LINK** says "now with battery hatch" !

[Piers Bowlan]

Posted by Low pass Pete on 31/01/2020 05:48:15:

Just been reading this whole Blog with interest. Also have looked at the Hobbyplastic site as well. They actually quote a Saito 82 not a 62. I have a Hangar 9 50in Corsair and that had a Saito 82 which was ok but now fly's better on an OS70.

Looking at the specs for the VQ Hurricane 60 I would personally put nothing less than a 91 4 stroke and think an OS95V or a Laser100 would be much the best choice of IC engines that are available to buy new today. Now way wouId a Saito 82 fly this model well. I have a H9 Thunderbolt 63in that has an OS 95V upfront and that is a good match. Richard's comments seem very informative and helpful.

Sorry I cannot help on electrics but as you probably gathered I'm not into electric so far and all this makes me think twice especially for a warbird.

Good Luck and best regards

Peter

 

Thanks for that Pete, I think I had a momentary aberration and was looking on the Hobby Plastics site at the VQ 46 Hurricane for Saito 62. Yes, Saito 82 makes a lot more sense. DOH!

So back to 6s , a suitable prop and some way of squeezing the battery into the nose beneath the motor....or alternatively, fitting a Laser 100 .

STOP PRESS:- Laser 80s and 100s are back in stock!!

Edited By Piers Bowlan on 31/01/2020 11:55:46

[Ronos]

Here goes guys, 6s 5000mAh here are the results.

69A and 1500w on a 14x7 APC electric prop. Full throttle 

Edited By Ronos on 31/01/2020 15:25:23

[Bob Cotsford]

1500W? at least you have a throttle! That is verging on 3D power levels.

[Ronos]

Posted by Bob Cotsford on 31/01/2020 15:25:06:

1500W? at least you have a throttle! That is verging on 3D power levels.

Yeah plenty of power there now, not that I will be flying at full throttle anyway but nice to have a bit in reserve.

[Piers Bowlan]

If a 6s doesn't fit in the cowl beneath the motor would a 5s LiPo fit, with some surgery to the forward bulkhead? Looks like you might have some headroom regarding power from your motor there, so 6s may not be necessary and 5s might be the sweet spot regarding obtaining enough power from your set-up on the one hand and squeezing a battery into the space as far forward as possible, to negate having to bolt large quantities of church roof in the nose.

[Ronos]

Piers, that came to me also, but truly there is no room, it's going to have sit behind the bulkhead. As far as the extra weight, the powers there and am used to something coming in hot with the mozzie.

Anyway I know where am at now and what I need. Once again a big massive thanks for all you guys info and knowledge, I have learnt a lot, Ron.

[Ronos]

Posted by Richard Wills 2 on 31/01/2020 05:32:08:

I have both the 46 and 60 VQ Hurricane, and I think the specs on the site are wrong, they match what the 46 acually weighs. The 60 came in at 10.5lb

My 60 has a 91 FS engine and 19oz of lead bolted onto the engine mount total of 43oz, but I have moved the cg back a little from the manual. The electric motor is 10oz so total of 50oz on the front, so not far out of what I have if you are on the marks.

I get 8300rpm on a 14x8 and to be honest it is marginal for power, no way it would fly on a 62 so that info is probably for the smaller one too. The pitch speed is fine, but needs more thrust so I would try 15x8 or 16x8 and see what numbers you get as you seem to have some head room.

It flies great but it is heavy so watch it. The stall when it comes is vicious so careful on that elevator, the manual throws at 10mm are generous.

Edited By Richard Wills 2 on 31/01/2020 05:32:57

Edited By Richard Wills 2 on 31/01/2020 05:37:06

Hi, could you tell me CoG you ended up with, I have mine on the 90mm mark.

[Ronos]

Hi all, just a small update. Like I said the 6s is getting me about 1500 watts with a 14x7 APC electric prop. I have managed to get the lipo as far forward as possible by cutting out a bit of the fire wall, and it took 16oz of lead to get it balanced with a 2lb lipo in, but that didn't get any weight off, still comes in at 4.5kg.

[Eric Robson]

Hi Ronos and all, being new to the forum I have just noticed this thread. I too have a VQ HURRICANE 60 and reading their advert I thought it was also designed for electric. The mount and screws come with it for both ic and electric but no easy way of replacing the battery. after looking at how to do it I decided to go i.c. I used a RCV 91. which is heavier than my Saito 125 but still had to put 500grms. of lead up front. The first flight in a steady breeze was ok nothing spectacular and very little reserve power the next time I went flying it was very calm and it only just managed to get off the ground. once up it flew better in the calmer conditions .The nose is about 30mm longer than scale so imagine how much lead that would need if it were the right length, I am still thinking of going electric but did not fancy cutting all the bulkhead away or taking the wing off to change the battery. I have an Overlander Thumper motor which I think is the same as the elecrospeed boost motor the numbers are the same they look the same the label's are the only difference. looking at your last post has given me food for thought that should fly it no problem.

Scrolling down the advert for the Hurricane there is a video of one flying very well with an ASP 61 FS. no details of weight . Eric r.

[Ronos]

Hi Eric, yes I agree, it's not very electric friendly, not like the FW190 which comes with a battery holder and theres a door behind the exhaust to get at the lipo. What I did was basically cut a opening the same dimensions as the lipo in the fire wall, made a battery tray and strengthened the sides with light ply and put a stopper behind the motor mont to stop the lipo touching the motor shaft. The bottom of the battery tray came in handy for the extra lead needed to get the CoG. I will post some photos later.

[Eric Robson]

Hi Ronos, the wind eased a bit today so I took my Cambrian large scale ME 109 for its first flight. When I arrived at the flying site the wind had picked up again I decided to try any way. It has a 5055/06 motor with a 16x10 prop and a 5s 5000 lipo it is 22 ozs. lighter than the Hurricane with the battery in, as it turned out there was too much power even in the strong wind I had two flights on the 5s batteries I had two 6s with me but did not use them as it meant changing the prop and it was getting colder in the wind I was getting about 1200 w on this set up . At the moment I will wait till the weather warms up before testing the other options with the watt meter. I have electric retracts in and used the supplied undercarriage fixed legs from the Hurricane and even with two good landings they bent back like they were soft wire I will have to use 5mm for the next flight ,I think they would collapse under the Hurricane.

Keep us informed how it performs when the weather improves.