Top rc full composite 89" blondie p-51d
#51
Member
Join Date: Sep 2005
Location: Richmond,
VA
Posts: 50
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://www.rcuniverse.com/forum/images/icons/icon1.gif)
I'm glad to hear we made good choices! In my haste to get my mustang project underway, I didn't research enough to find out that a DLE55RA running a 4 blade Beila prop with a 2.5 lbs of spinner and electric start hardware is probably not a good choice. I would like to keep the scale look and flight performance as much as possible. The recommended 4 blade prop size for the DLE55RA is a 19x8 which is about 1/7th scale. Thats way too small in my limited opinion. A 1/5 scale prop for P-51D is about 26.5 inches which would require a much larger engine to swing it. Can someone recommend an engine/prop combo I do some scale flying with? I estimate the all up weight will be about 31 lbs.
Regards,
Keith
Regards,
Keith
#54
![](/forum/images/badges/trading_plus_member.png)
My Feedback: (3)
![Default](https://www.rcuniverse.com/forum/images/icons/icon1.gif)
kcollier,
I have done a lot of 4 blade testing with both gas engines and electric brushless motors. I hate to burst your bubble but the engine you want to use is about 40-60 cc too small for a scale sized prop on your Mustang. The main problem is the power pulse the gas engines punch the prop with requires that the hub and blades be over-sized in construction to avoid a catastrophic blade loss that will destroy the entire plane if (MORE LIKE WHEN) it happens. This heavy, thick hub and blade construction needs lots of excess horsepower just to turn it, and a lot more horsepower for scale like performance. My big gas 4 blade prop is a wall ornament (22-14 blades), it needs a 110cc twin for adequate flight performance.
I have had, however exceptionally good performance with the Varioprop (Germany) brand with electric brushless motors turning them. An 80 mm diameter or larger motor can spin them but you need to carefully match the motor's top rpm (KV) with the design top rpm the manufacturer lists as max for their product. I used the 22.6 inch diameter blades (max 4900 rpm for 1 minute) but found that the electric motor over revved the prop during the takeoff (stalled blade airfoils) and again at high speed even with the pitch set at 18 inches. I bought a set of (19.9 inch diameter) Spitfire blades rated for higher rpm's but they didn't look as good as the 22.6 inch Hamilton Standard set. The 19.9 blade set worked very well for takeoff power (pitch set at 18 inches) and high speed flight (130+mph). Current draw was high (140-165 amps) during acceleration but dropped dramatically during cruise even at 120+mph (65-85 amps). As an electric motor approaches its maximum rpm it unloads and current draw goes way down if you are using a clean airframe like the P-51. Round motored planes are going to be operating close to the motor's max current rating all the time because of the airframe drag, but they have more room for batteries. P-51 planes typically don't have enough internal room for the large (24 cell, 10,000 mah) LiPo packs needed for 10 minute duration. My P-51B weighed 29.5 lbs with a 24 cell 6600mah pack and gave me 5-7 minute flights.
If you are going to want to stick to gas power then you need to use the 100 inch wing span class of plane and 100-120cc twin cylinder motors for power. At that size it all gets easier, especially if you can keep the gross weight down below average (hard to do with gas power).
I have done a lot of 4 blade testing with both gas engines and electric brushless motors. I hate to burst your bubble but the engine you want to use is about 40-60 cc too small for a scale sized prop on your Mustang. The main problem is the power pulse the gas engines punch the prop with requires that the hub and blades be over-sized in construction to avoid a catastrophic blade loss that will destroy the entire plane if (MORE LIKE WHEN) it happens. This heavy, thick hub and blade construction needs lots of excess horsepower just to turn it, and a lot more horsepower for scale like performance. My big gas 4 blade prop is a wall ornament (22-14 blades), it needs a 110cc twin for adequate flight performance.
I have had, however exceptionally good performance with the Varioprop (Germany) brand with electric brushless motors turning them. An 80 mm diameter or larger motor can spin them but you need to carefully match the motor's top rpm (KV) with the design top rpm the manufacturer lists as max for their product. I used the 22.6 inch diameter blades (max 4900 rpm for 1 minute) but found that the electric motor over revved the prop during the takeoff (stalled blade airfoils) and again at high speed even with the pitch set at 18 inches. I bought a set of (19.9 inch diameter) Spitfire blades rated for higher rpm's but they didn't look as good as the 22.6 inch Hamilton Standard set. The 19.9 blade set worked very well for takeoff power (pitch set at 18 inches) and high speed flight (130+mph). Current draw was high (140-165 amps) during acceleration but dropped dramatically during cruise even at 120+mph (65-85 amps). As an electric motor approaches its maximum rpm it unloads and current draw goes way down if you are using a clean airframe like the P-51. Round motored planes are going to be operating close to the motor's max current rating all the time because of the airframe drag, but they have more room for batteries. P-51 planes typically don't have enough internal room for the large (24 cell, 10,000 mah) LiPo packs needed for 10 minute duration. My P-51B weighed 29.5 lbs with a 24 cell 6600mah pack and gave me 5-7 minute flights.
If you are going to want to stick to gas power then you need to use the 100 inch wing span class of plane and 100-120cc twin cylinder motors for power. At that size it all gets easier, especially if you can keep the gross weight down below average (hard to do with gas power).
#55
![](/forum/images/badges/trading_plus_member.png)
My Feedback: (207)
![Default](https://www.rcuniverse.com/forum/images/icons/icon1.gif)
I'm glad to hear we made good choices! In my haste to get my mustang project underway, I didn't research enough to find out that a DLE55RA running a 4 blade Beila prop with a 2.5 lbs of spinner and electric start hardware is probably not a good choice. I would like to keep the scale look and flight performance as much as possible. The recommended 4 blade prop size for the DLE55RA is a 19x8 which is about 1/7th scale. Thats way too small in my limited opinion. A 1/5 scale prop for P-51D is about 26.5 inches which would require a much larger engine to swing it. Can someone recommend an engine/prop combo I do some scale flying with? I estimate the all up weight will be about 31 lbs.
Regards,
Keith
Regards,
Keith
#57
![](/forum/images/badges/trading_plus_member.png)
My Feedback: (3)
![Default](https://www.rcuniverse.com/forum/images/icons/icon1.gif)
TimD,
Kcollier was asking about running a SCALE sized prop which would have a diameter of 26+ inches. I have a ZDZ 80RV which easily turns 26-12 2 blade or 24-12 3 blade with incredible speed and vertical performance, but it can't do as well with a 4 blade prop. Your DA 85 will turn an UNDERSIZED 4 blade prop but he was asking about WHICH engine would turn a SCALE sized prop. Not the same thing. Electrics can turn a scale diameter ELECTRIC prop but these props can't be bolted onto a gas engine, they don't have the structural strength to withstand the gas engine's power pulse. My ZDZ engine's power pulse is so strong that it throws the blades of some of the gas WOOD props that are recommended for it. I have the scars on my fingers as a result of blade loss on starting.
To get SCALE performance on a SCALE sized 26 inch diameter prop the minimum displacement is 100cc+ and a 2 cylinder engine with the firing order arranged at 180 degrees (2 firing events per revolution 180 degrees apart) would work better and have a smoother power delivery than a big single. Even twins that have both cylinders firing simultaneously have a destructive power pulse.
The MOKI radials can turn 4 blade props with scale diameter but these engines don't fit the nose of a Mustang. DA makes a custom built 100cc+ inline twin that can do the job in a Mustang but a complex baffle system is needed to keep it cool. I have had to be satisfied with the smaller than scale Varioprop designed electric props to match the 65cc electric motors (6000+ watts, over 8 horsepower) and I have tested Zinger wooden 22-16 4 blade props (7400 watts, almost 10 horsepower). The Zinger flew the 30lb. plane well but speed was down to about 105 mph and constant current draw at all throttle settings was too high for the electric systems to be able to withstand for more than 3 minutes. A 100cc+ gas twin is capable of turning this size 4 blade (22-16) but this is still not a scale sized prop. Flight performance with the Zinger 22-16 (it needs 10 horsepower) is adequate but I too want a scale sized 4 blade on the front of my warbird.
I have a set of Zinger 24-16 blades (for gas engines) but the power requirement is too great for any power system I now have, and they are still smaller than scale size. I have looked long and hard at the Biela 4 blades but they aren't scale sized and are built for gas engines so would have excessive current draw on my electric motors.
The Canadian built 110cc Widowmaker 4 stroke, 4 cylinder is promising in a Ziroli 98 inch wingspan model but, for me, bolting on a $5,000+ power system is more than I want to risk losing in a crash. There are some European built Inline 4 stroke, 3 and 4 cylinder engines available that have demonstrated the ability to turn large props and both the SOLO and Varioprop gas props can and have been used on them because these props have ground-adjustable pitch (again, high cost). The need for much higher pitch is there because the large 4 blade scale sized props lug the motor rpm down so much that any pitch below 14 inches (Biela) won't even reach Scale speed, (75-90 mph) in the 1/5 to 1/4 scale warbird.
There is an American-made 2 and/or 3 cylinder gas 2 stroke in-line engine that the pylon racers use but this is a Ziroli warbird sized engine, and from what I have seen, its in-flight reliability stops me from trying it (most of the flights I have personally witnessed ended in a dead stick landing with gear and wing damage). To me, 100% power plant reliability is paramount in these high value airframes that don't glide when the motor stops before the landing. This is why I have stuck to using DA engines in my expensive warbirds. The flyaway total cost of my electric P-51B at $4,500 is almost too much to risk (for me). And I have had almost 100% reliability with my electric power systems to date, even when I had an in-flight failure of a 4 cell LiPo pack (1 of six), I was still able to have a powered approach to a successful landing.
I have sold my Zinger 4 blade prop to someone else who wants to try it on a large gas engine.
Kcollier was asking about running a SCALE sized prop which would have a diameter of 26+ inches. I have a ZDZ 80RV which easily turns 26-12 2 blade or 24-12 3 blade with incredible speed and vertical performance, but it can't do as well with a 4 blade prop. Your DA 85 will turn an UNDERSIZED 4 blade prop but he was asking about WHICH engine would turn a SCALE sized prop. Not the same thing. Electrics can turn a scale diameter ELECTRIC prop but these props can't be bolted onto a gas engine, they don't have the structural strength to withstand the gas engine's power pulse. My ZDZ engine's power pulse is so strong that it throws the blades of some of the gas WOOD props that are recommended for it. I have the scars on my fingers as a result of blade loss on starting.
To get SCALE performance on a SCALE sized 26 inch diameter prop the minimum displacement is 100cc+ and a 2 cylinder engine with the firing order arranged at 180 degrees (2 firing events per revolution 180 degrees apart) would work better and have a smoother power delivery than a big single. Even twins that have both cylinders firing simultaneously have a destructive power pulse.
The MOKI radials can turn 4 blade props with scale diameter but these engines don't fit the nose of a Mustang. DA makes a custom built 100cc+ inline twin that can do the job in a Mustang but a complex baffle system is needed to keep it cool. I have had to be satisfied with the smaller than scale Varioprop designed electric props to match the 65cc electric motors (6000+ watts, over 8 horsepower) and I have tested Zinger wooden 22-16 4 blade props (7400 watts, almost 10 horsepower). The Zinger flew the 30lb. plane well but speed was down to about 105 mph and constant current draw at all throttle settings was too high for the electric systems to be able to withstand for more than 3 minutes. A 100cc+ gas twin is capable of turning this size 4 blade (22-16) but this is still not a scale sized prop. Flight performance with the Zinger 22-16 (it needs 10 horsepower) is adequate but I too want a scale sized 4 blade on the front of my warbird.
I have a set of Zinger 24-16 blades (for gas engines) but the power requirement is too great for any power system I now have, and they are still smaller than scale size. I have looked long and hard at the Biela 4 blades but they aren't scale sized and are built for gas engines so would have excessive current draw on my electric motors.
The Canadian built 110cc Widowmaker 4 stroke, 4 cylinder is promising in a Ziroli 98 inch wingspan model but, for me, bolting on a $5,000+ power system is more than I want to risk losing in a crash. There are some European built Inline 4 stroke, 3 and 4 cylinder engines available that have demonstrated the ability to turn large props and both the SOLO and Varioprop gas props can and have been used on them because these props have ground-adjustable pitch (again, high cost). The need for much higher pitch is there because the large 4 blade scale sized props lug the motor rpm down so much that any pitch below 14 inches (Biela) won't even reach Scale speed, (75-90 mph) in the 1/5 to 1/4 scale warbird.
There is an American-made 2 and/or 3 cylinder gas 2 stroke in-line engine that the pylon racers use but this is a Ziroli warbird sized engine, and from what I have seen, its in-flight reliability stops me from trying it (most of the flights I have personally witnessed ended in a dead stick landing with gear and wing damage). To me, 100% power plant reliability is paramount in these high value airframes that don't glide when the motor stops before the landing. This is why I have stuck to using DA engines in my expensive warbirds. The flyaway total cost of my electric P-51B at $4,500 is almost too much to risk (for me). And I have had almost 100% reliability with my electric power systems to date, even when I had an in-flight failure of a 4 cell LiPo pack (1 of six), I was still able to have a powered approach to a successful landing.
I have sold my Zinger 4 blade prop to someone else who wants to try it on a large gas engine.
Last edited by sjhanc; 08-10-2016 at 09:45 AM.
#58
Member
Join Date: Sep 2005
Location: Richmond,
VA
Posts: 50
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://www.rcuniverse.com/forum/images/icons/icon1.gif)
Thanks for the info guys. It's good to hear from first hand experience. The DLE85 seems to be a good compromise between scale and performance and looks.
TimD, Can you post a pic of the Jtec muffler modification to the cowl? Thanks
TimD, Can you post a pic of the Jtec muffler modification to the cowl? Thanks
#66
![](/forum/images/badges/trading_plus_member.png)
My Feedback: (3)
![Default](https://www.rcuniverse.com/forum/images/icons/icon1.gif)
I have this Zinger 4 blade 22-16 prop with a spare set of 24-16 blades. I painted the 22-16 blades and applied nomenclature and Hamilton standard decals as you see in the picture. The prop was balanced by applying GOOP to the light blade hub. I flew the 22-16 for one test flight on my electric 29.5 lb. TF GS P-51B, then installed a 22.6-18 Varioprop next to compare flight characteristics and performance between the two brands. The electric Varioprop won on lower current draw in level flight so I went on to fly many flights with the electric-Varioprop combination. Different blade combinations could be made using the DB hub for a drill jig and cutting four 2-blade props to fit. It is possible that Dave Drown products could supply replacement blades if they are still in business but it was my understanding that each 4 blade prop was custom made-to-order.
Flying performance with the Zinger was good (85+ mph) but the Varioprop suited my B model the best so this Zinger has been a wall ornament after the one test flight. My best estimate of a suitable engine for this prop is a 100-120cc gas engine is required for best performance. Engines like a DA 85 or ZDZ 80-90 would give scale like flight performance with top speeds of over 75-80 mph in level flight. The electric power combo reached 100-105 mph in level flight but continuous current draw (130-140 amps) was too high for the electric motor. Takeoff current draw reached 165 amps until the gear was retracted then dropped to the level flight range.
If anyone is interested I will post it for sale (bids) in the classifieds. I cut up an old Dave brown 5 inch P-51 spinner for it and also had to enlarge the hub's front prop plate hole to be able to be able to use a countersunk prop nut and washer as the hub is thick and normal engine or motor shaft length is too short for the stock prop nut and washer. I think I still have the modified prop nut and washer, but it would take a search to find them. The Dave Brown Products nut I used had a 10-1.25 mm thread and was turned down by a private machine shop to allow the washer to fit high on the nut's shank and is a tight fit inside the prop hub's front plate. The prop came to me assembled by Dave Brown products in a large shipping container and I have not taken it apart. It could be dissembled for easier and cheaper shipping. I have recently sold the Zinger 4 blade to someone who want to try it on a large gas engine.
Flying performance with the Zinger was good (85+ mph) but the Varioprop suited my B model the best so this Zinger has been a wall ornament after the one test flight. My best estimate of a suitable engine for this prop is a 100-120cc gas engine is required for best performance. Engines like a DA 85 or ZDZ 80-90 would give scale like flight performance with top speeds of over 75-80 mph in level flight. The electric power combo reached 100-105 mph in level flight but continuous current draw (130-140 amps) was too high for the electric motor. Takeoff current draw reached 165 amps until the gear was retracted then dropped to the level flight range.
If anyone is interested I will post it for sale (bids) in the classifieds. I cut up an old Dave brown 5 inch P-51 spinner for it and also had to enlarge the hub's front prop plate hole to be able to be able to use a countersunk prop nut and washer as the hub is thick and normal engine or motor shaft length is too short for the stock prop nut and washer. I think I still have the modified prop nut and washer, but it would take a search to find them. The Dave Brown Products nut I used had a 10-1.25 mm thread and was turned down by a private machine shop to allow the washer to fit high on the nut's shank and is a tight fit inside the prop hub's front plate. The prop came to me assembled by Dave Brown products in a large shipping container and I have not taken it apart. It could be dissembled for easier and cheaper shipping. I have recently sold the Zinger 4 blade to someone who want to try it on a large gas engine.
Last edited by sjhanc; 08-10-2016 at 09:47 AM.
#67
![](/forum/images/badges/trading_plus_member.png)
My Feedback: (48)
![Default](https://www.rcuniverse.com/forum/images/icons/icon1.gif)
Finishing up install of a ZDZ80RV to replace my DLE85 on a Ziroli size P51. The JMB Pitts type muffler required extensive cutting of the cowl side. The ZDZ has a narrower exhaust flange than the DLE85 so engine with a unmodified JMB muffler fit very well with no cutting of cowl for muffler. I did tilt engine about 5 degrees to help.
I flew with a 26/10 2-blade Xoar but will be trying the Biela 23/10 4-Blade
I flew with a 26/10 2-blade Xoar but will be trying the Biela 23/10 4-Blade
Last edited by dmyers0403; 07-31-2016 at 06:02 PM.
#69
![](/forum/images/badges/trading_plus_member.png)
Join Date: Sep 2009
Location: Monroe,
NC
Posts: 2
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://www.rcuniverse.com/forum/images/icons/icon1.gif)
Have you thought about a reduction drive? This will reduce the engine RPM to a safe RPM for a scale 4 blade propeller. This will also stop the blades from stalling out at maximum engine RPM.
#72
![Default](https://www.rcuniverse.com/forum/images/icons/icon1.gif)
Hii, sorry my bad english.
Not yet order, I want to perchase the Gunfighter color scheme of Top RC model's Mustang.
I want to know about the model shop name already in stock.
Not yet order, I want to perchase the Gunfighter color scheme of Top RC model's Mustang.
I want to know about the model shop name already in stock.
#75
![](/forum/images/badges/trading_plus_member.png)
My Feedback: (34)
Join Date: Dec 2001
Location: Modesto,
CA
Posts: 446
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://www.rcuniverse.com/forum/images/icons/icon1.gif)
Always nice to have options. I asked them about the Corsair that they are supposed to release but got not solid answer of a date. Maybe they are planing on different schemes for the P-51...would be a wise idea.
Thank you for posting!
Thank you for posting!