Eddie P

My Feedback: (4)

I'm putting a quick change external smoke tank on my TJ A-4, powered by a Wren Supersport. I have a Tamjets Smoke Pump.

In terms of ounces per minute of oil flow, what are you guys seeing that will work as far as laying a decently visible smoke trail? I was looking quickly at the manual for the pump and it looks like it can be set to a pre set level and switched on or off or alternatively can be variable pump rate slaved to throttle or even using a slider depending on setup.

I don't need to smother skies with massive smoke like a biplane doing snap rolls and such but a good respectable trail would be nice. I'm using the standard Tamjets steel smoke nozzles. I've read where guys are further pinching them with a exacto blade inside to keep them very restricted to spray the oil better in the exhaust flow and have seen posts showing the importance of the placement of the smoke nozzle on the flow. Seems to make sense. I am in the process of building the tank in the next few weeks and I have some flexibility in the tank size since I'm fabricating it. I was hoping 20-24 ounces of smoke oil should be enough? I don't want too much extra weight since the jet is not a giant scale setup! But I'd like about 2 minutes of smoke if I could get it, to make the whole thing worth while on a 7 minute flight.

Here is a diagram of the tank. The reason for the two tanks inside is for baffling and to keep air bubbles/smoke interruptions down during accelerations/decelerations/aerobatics. Also I can use cheap off the shelf plastic tanks and use inexpensive parts on hand for the tank fairing as this is a light wright quick build tank. Originally I had the pump co located in the tank fairing but decided to locate it on a quick remove mount in the engine bay to reduce the loading on the tank installation to just smoke oil mass alone. The tank pylon is mounted to bracing attached to the formers and braces in the airframe, and will be semi permanent while the tank fairing itself is a quick connect to the pylon. TIA for any thoughts.

EDIT: Smoke Tank re designed. Thanks Wayne for picking up on the errors in my initial design and letting me know on post 5!

FalconWings

My Feedback: (57)

Eddie, everyone will have a different setting based on their own plumbing techniques. It is really trial an error.

In my Tamjets F_16 I had a Tam smoke pump and 16 oz of smoke oil. I had the setting for 30 seconds of very dense smoke, and boy was it dense!!
Others could get more than one minute on a similar setup. So really, just go up and adjust to your taste.

Regards,
David

Eddie P

My Feedback: (4)

Thanks! Dang, smoke oil doesn't last long at all! I might have to re-think that 8 ounce hopper tank as a secondary 16 ounce tank for 32 ounces total!! Good news is that it would be an easy mod to up the capacity if I go that route. I suppose I'll start with 24oz and go from there.

What's the lowest throttle setting reliable and (relatively) clean smoke can be had? I assume smoke is best to use at higher throttle settings...

smitty1001

My Feedback: (29)

Eddie,

Actually the best, thickest smoke is at lower throttle settings, it is thicker and whisps in the wake of your jet. Full throttle smoking requires perfect placement, atomization and quality oil to not thin out on you. Experimentation is going to be key. Sounds like you have a good start.

James

FalconWings

My Feedback: (57)

Eddie, you really don't need that much, but it depends on your flying style. I like to try to ressemble the Thunderbird, pretty much smoke on when doing the maneuver then smoke off upon completion. It looks really good when you nail it down, but it takes a while to master. I.e. try turning smoke on while inverted, not as easy as it seems.I see a lot of people that leave it on until it runs out. It's ok but for that you really need lots of fluid. 30 seconds of smoke was really all I needed to do a small aerobatic sequence.

What James said is true. At idle and slow airspeed smoke is awesome. You can even light up a flame that will look like an AB, just don't try it on purpose, as your tailpipe gets it!!

Wayne22

My Feedback: (2)

I figure on 16oz a minute on the wren. I have mine hooked to a slider so the smoke volume can be varied according to the circumstances. If you are practicing some maneuvers, you can thin it out, but if the Swedish Bikini Team stops by the field, you can crank it up...

I'd get about 3 1/2 minutes of off and on smoke in a 6 minute flight on 32oz.

BTW, in your plumbing diagram above, the front tank would never fill completely unless the inlet line to the second tank was moved up to the top.......

Eddie P

My Feedback: (4)

Thanks for the feedback!

Also, good heads up on the tank plumbing - I'll have to re design to feed oil to the header tank with an oil fill line - and then feed the main 16 oz oil tank with the header tank vent out the top. Like this: Fill line to header tank > Header tank full > Header tank vent to main tank > Main tank fill up to main tank vent. For feed: Feed from header tank pickup klunk to smoke pump and nozzle. Header tank stays full by pulling oil from the main tank via main tank klunk feeding header tank inlet vent until it's empty, then header tank empties last.

I'll have a shut off valve to the smoke pump so I can fill the tanks without oozing smoke oil past the pump.

Eddie P

My Feedback: (4)

Edit: Dreaded double post from slow network!!

Jetpilot24

My Feedback: (21)

Eddie

I have a quick release smoke tank on my F-15. The tank holds the smoke oil tank (32 oz.) the smoke pump and the battery for the system. I get about 3-1/2 minutes on the smoke if I leave it on all the time.

I have a setting of 55% on my travel adjustment for the smoke pump. Also I run the injector down between the double wall of the tail pipe and spray behind the pipe and I get plenty of smoke. I don't like the Idea of possible oil laying in the pipe.

In the video here I am using the Concrete form release oil for smoke oil. I have found that it does not smoke as well as the commercial grades such as super dri or the like.

http://www.youtube.com/watch?v=iEKASGZTPsE

Joe Lewis
Kingtech
K-80 and K-140
Owner

Eddie P

My Feedback: (4)

Joe that is so cool! I love the idea of the smoke tubes going to the aft end of the pipe! Clean and care free in my book - awesome, thanks for the pics. I'm gonna have to experiment with that. What brass tube size are you using and how did you secure the brass tube to the SS tube near the aft end of the exhaust? (It almost looks like it's the same brass tube at the exhasut end - not using SS? I assume it works and doesn't melt as it's still working!!)

PS - sweet video. I like the gap between the pipe and the smoke in this setup - looks like a real jet with smoke or a contrail.

PaulD

My Feedback: (39)

I run about 12 oz per minute thru a single stainless nozzle with the end crimped flat over a blade tip. Have a bit of a mix so the smoke pump increases with throttle somewhat. It is harder to get the dense smoke with higher speeds. Smoke fluid is form oil with some additives or I have even just run diesel with some light oil added to help it "hang".


http://vimeo.com/26703755

PaulD

Jetpilot24

My Feedback: (21)

PM Sent

smchale

My Feedback: (67)

Can you share your answer to this? I'm looking to set up my first smoke system and any tips are helpful.

Eddie P

My Feedback: (4)

For sure Sean, expect some more as I learn.

Joe, thanks very much, will chat soon!

Nice smoke video Paul, thanks for the tips as well.

I updated my schematic above to this one to clean up my sloppy plumbing design that would not work well. Thanks again Wayne for pointing out the problem areas!

Wayne22

My Feedback: (2)

that looks better!!