Precedent Stampe 1/4 Scale

[Steve Dunne]

Hi Cymaz, Stuphedd, Thanks for the responses.

I have seen the various posts before, from several members who have used the gas struts. I was asking those who have used them what strength struts they have found successful There is a very large range of sizes and strengths, and just wanted to hear from some actual experience of using the struts. Then I have a start point without buying baskets full of struts.??

[Stuphedd]

Mine is 60 nm on the Stampe , photos are in this thread a long ways back 

[martin collins 1]

Just picked up a used Precedent Stampe yesterday, will post some pics later, i want to put a petrol motor in it (used one as watching the pennies now i am retired), the firewall has a wooden mount built onto it which apparently is too far forward and narrow to accept my first choice which is a Zenoah 38. A club mate has offered me a DLE 30 he is selling but i don`t know much about those and one that was used at our club had running issues, i gather these were traced to a leaking fuel supply pipe but i don`t want to buy an engine that is going to be more grief than it is worth. Thoughts on the engine in a Stampe and DLE 30`s in general? Anyone on here got one in their Stampe?...........

[Steve Dunne]

Hi Stupphed, thanks for the rsponse - and the photographs. Very helpful, just what I was looking for!

 

Steve

[Stuphedd]

yep Martin  I have a DLE30 in my Stampe , look in this thread about a year or so back to see the detail ! Its is out of my Turbo Porter and never missed a beat  and also have a DLE 30 in my Waco which has been equally reliable !Just had to make up exhaust stacks for the models! 

[cymaz]

Go with the dle. Lots of spares, easy to set up and there'll be plenty of knowledge on the forums

[martin collins 1]

Looking at the dimensions i think i will have to use shorter 50mm stand offs to get the prop where it needs to be and maybe enlarge the hole for the carb in the firewall.

Are standard Futaba 3001 or 3003 type servos ok to use, it will see only mild aerobatics, loops, rolls, stall turns etc? 

Edited September 9, 2021 by martin collins 1

[Martin McIntosh]

You will replace the silicone for petrol tubing in that SLEC tank won`t you?.

[martin collins 1]

I didn`t think you could use those SLEC tanks with petrol anyway, the seal would perish? I was going to replace the whole tank...............

[Nick Somerville]

Martin, I saw the ad for the Stampe you have acquired and it looked nicely finished. bargain price too! DLE Petrol will power it ok but just won’t give you or anyone else at the field the enjoyment of watching/listening to a classic biplane flying with an authentic sound. Find a second hand 150-180 fourstroke that suits the firewall and you won’t regret it. I have a Laser 180 glow in mine and every time I fly it people comment on the realism of engine note. Someone at the club has a ngh 30cc petrol 4 stroke in a Fokker triplane and that sounds pretty good too, if petrol is what you want.

[martin collins 1]

Thanks for the advice Nick but i haven`t flown glow in twenty years as i can`t stand the oily mess, i won`t be going back there. Most of my planes are electric but am just getting back into petrol for the large ones.

[Engine Doctor]

Seems to be a theme ? I bought an old  Precedent Stampe from a club matewho inturn had bought it from a dealer as I wanted the Enya 120 4c in it. Got it for a good price and intended to dispose of air frame but it was too good. Have now got it airworthy but have swapped out the Enya for a ASP 91 as the Enya had a tendency to throw its prop. More on that later. 

If weather is OK this weekend it will hopefully get in the air. Will add dome pics later and hopefully the builder will recognise it .

[Martin Harris - Moderator]

Re. some of the comments about scale speed and prompted by Jon’s mention of Old Warden, I recall watching, from the cafe, a (sadly no longer with us) club member’s Precedent Stampe (120 FS powered) flying during one of the Schools Days that we used to help out at. I had to look carefully to ensure it was his model and not a similar looking full size!  He’d built it lightly with little additional detailing but it always struck me how scale like his flying was with it. I suspect it flew on a relatively low pitched prop to assist in giving realistic performance. 
 

I have no idea whether the model survived him as he sold up and spent his last years living on a small yacht in the Caribbean - plain silver grey with a penguin motif on the tail if memory serves correctly- but it was certainly proof that these models don’t have to be flown too fast. 

[Peter Jenkins]

I can now report that I have flown my Stampe with both the OS 155 and then replaced the OS 120 and flew that.  Both were successful.

 

Yes, it needed a lot of down trim but that has now been adjusted into the system so that the subtrim and trim is back to zero.  The ailerons needed a fair bit of trimming so the aircraft would fly straight – suspect there is a warp in the wing(s) but have not looked for it yet.

 

The first attempt to fly the Stampe resulted in the OS 155 not starting!  Traced that to a split in the fuel pipe feeding the pump.  So, I replaced all the plumbing and fitted 2 square SLEC tanks – 9 oz on the top and 6 oz on the bottom of the motor box where the original tanks had been.  I carried out the first flight but Ron wasn’t able to be there to film proceedings.  However, with the 155 running rich I suffered an engine cut as I did a high overshoot.  Thankfully, there was a strong wind blowing slightly across the strip so I was able to land on the full size grass runway about 150 yds away from me.  I made sure there was plenty of airspeed in the glide and the round out proved to be about right with the aircraft settling on a soft 3 point landing.  It was quite clear that the CG was far too forward – it balanced on the rear of the 2 top wing bolts.

 

I decided to put the 120 back in and eventually traced the problem of it not running due to the fact that the idle needle had to be unscrewed 2.5 turns in order for the engine to run.  I had assumed the previous owner had actually left the settings for the idle from when he last flew it but clearly this was not the case!  I removed one strip of stick on lead weights with the aim of gradually removing this ballast until I reached a CG that I feel is right.

 

I noted the tendency of the aircraft to pitch up on applying power.  So, having removed the 155 I fitted a couple of plastic down thrust ramps that I’ve had for ages.  These were set to give 3 deg of down thrust.  On the 2nd flight, (first for the 120) I was faced with a 60 deg cross wind 13 gusting 15 mph.  As you will see from the video, ably shot and edited by Ron, that I didn’t apply sufficient into wind aileron!  However, once I corrected that the take off went off fairly smoothly.  I had re-done the elevator linkage and gone back to zero trim but the aircraft still needed a lot down to fly level on half throttle.  It is also clear that some coupled aileron and rudder will help to overcome the small amount of adverse yaw that remains despite there being a good amount of aileron differential to begin with.  Interestingly, the combined 15 oz tank took 68 cranks to fill but after 8 mins of mostly half throttle flight, the refill was complete after only 12 cranks!  So, I probably don't need 2 tanks and will remove the bottom 6 oz tank and replace with the top 9 oz tank.  I would think that will give a comfortable 10 mins of flight.

 

The 3rd flight had a much better take off with a fair bit of into wind aileron applied from the beginning of the ground roll.  That flight also showed that even with full rates there was insufficient elevator authority to stall the aircraft and so it wouldn’t spin either.  I did try a few rolls but no loops.  In its current trim, the aircraft will fly inverted and using the rudder produces some passable axial rolls.  I have yet to try a loop as I’m conscious of all that’s been said about the strength of the wing!

All told, I was pleased with the aircraft and so now I’m going to set about some more detailed trimming starting with moving the CG back gradually until I can stall and spin the aircraft and it doesn’t need a huge amount of down to fly inverted.

 

Thanks to Ron Gray for videoing, editing and posting on YouTube.

[martin collins 1]

Link to the video on here would be good Peter ?

[EarlyBird]

 

[Peter Jenkins]

Thanks EB but the links are on the words "2nd flight" and "3rd flight" Martin. The line below the words signifies there is a hyperlink.  I did check both worked after posting as well.

[Ron Gray]

My apologies for the rather poor quality of vids, especially the second one during which the auto focus appeared to be reluctant to operate, likewise the image stabilisation!

[EarlyBird]

1 hour ago, Peter Jenkins said:

Thanks EB but the links are on the words "2nd flight" and "3rd flight" Martin. The line below the words signifies there is a hyperlink.  I did check both worked after posting as well.

No problem to me Peter I viewed them using your links. I copied and pasted your links to help @martin collins 1 

[Peter Jenkins]

Thanks EB.

[Martin McIntosh]

Hi PJ, if I were you I would leave the dual SLEC tank installation as is because it is identical to mine which works well. The cg on mine with a Laser 155 turned out to be 1" forward of the upper wing TE without ballast which is where most of us have it. Mine now has a much heavier Laser 180 but it still spins OK.

Mine rolls reasonably well for the aircraft type with 1" up, 1/2" down and unlike my Tiggy does not require any rudder coupling.

[Peter Jenkins]

Hi Martin, thanks for your observations.  I've decided to leave the tanks alone for the  time being, but only half fill them, but I did remove all the lead stick on weights that the first owner had installed.  I doubt that will move the CG back by much but I will be doing a balance check to see!  I've also now re-aligned the elevator pushrod geometry so that I am back to zero sub trim and zero trim to give an elevator position for S&L flight approx.  The next flight will allow me to fine tune that.  There is a good amount of aileron differential but it still looks like there is some adverse yaw.  Again, work in progress on that one and probably needs a calm day to check that.  

So, next flight will check if the aircraft will stall, if it will spin until recovery is initiated; whether the coupled aileron/rudder is right and fix it if not; and a check of CG position in flight.  I've always found that aircraft with too forward a CG and not nice to fly.  I will also be refining control throws for an intermediate rate as opposed to full rate.  The 3rd and even lower rate will wait until the aircraft feels less leaden footed to fly.

[martin collins 1]

Still pondering which petrol engine to use, looks like it will have to be a rear exhaust engine to avoid having to make/buy an expensive custom made one as they all seem too wide. The current firewall is also too small to accept both a DLE or a Zenoah so the engine length issue i had will now not be a problem. Anyone on here got theirs fitted with a Zenoah 38 with rear exhaust? Does that fit in the cowl ok? Other current option is a DLE 30 or 35 with rear exhaust, engine will have to be a used one as the budget does not stretch to the new prices...........Martin

[john stones 1 - Moderator]

Would a wrap around Pitts exhaust fit in cowl on a side exhaust engine, plenty of sellers about.

 

https://www.justengines.co.uk/product-category/exhaust-systems/two-stroke-exhausts/incowl-mufflers/ngh-wrap-arounds/?v=79cba1185463

[cymaz]

There is a DLE 30 for sale on  the BMFA classifieds, £130