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I pulled a Jeff and got a new project: ESM 71" SBD-5 Dauntless

willsonman

willsonman

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The weight is not a big deal but I'll get to that in a minute.

To start the battery hatch off I added two ply plates between the firewall and the first former. I cut a slit in the top for the velcro straps. Installation is with Gorilla glue.
IMG_5977.JPG

Another ply plate is cut to accept the velcro and fitted with mating velcro.
IMG_5978.JPG

When the plate is pulled up there is easy ingress/egress for batteries so nothing has to leave the airplane.
IMG_5979.JPG

With batteries installed, the top plate presses down on them and keeps them from flopping around.
IMG_5980.JPG

The inside of the wheels needed a nylon washer so I added one.
IMG_5981.JPG

I formally marked the CG and have made further preparations... for the maiden. The winds keep changing on me for this weekend so we shall see.

Back to Rovers: I weighed is all and we are looking at AUW of 13.2 pounds. The recommended flying weight is 13.7 so o.5 pound under weight is a win in my book. Then couple that with the fact that this power setup came from my Hawk, which if I recall correctly is well above the 14 pound mark.
 
wilmracer

wilmracer

I build things that fly (sometimes)
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That wing area and loading is very reasonable for a big warbird. I peaked at the specs and you've got 821 sq. inches of area, which puts you at a cube loading of 15.5. Obviously the P6E has an extra wing and more wing area so the loading is higher, but that is to be expected. The Dauntless should have less drag (especially when retracts are fitted) so the power setup you've got should pull her around very nicely.

Can't wait to see her go!
 
willsonman

willsonman

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So, I went out to the field on Saturday with this one with the full intent to fly. Carl was eager to fly as well so he drove out to my field and there was a good gathering for my club. After initial taxi testing it was discovered that one of the landing gear blocks had split. It is solid wood and split along the grain. Another club member was nice enough to go out and pick up some CA and we had another go. The block did not split but the main block did separate from the mounting plate.

I went home and made new blocks and plates using all ply. I sandwiched 5 layers of ply using gorilla glue and clamped them well. I did this for both sides as it was likely to be a problem eventually for the other side. All back together, I met a club member at the field yesterday morning.

Another round of taxi testing showed that the blocks still separated from the plate. Fortunately, he had a couple of screws that I put through the mounting plate into the block. It worked and all that was left was to fly.

Lining up on the runway with a slight cross wind, I throttled up to find her strongly pulling to the left. I taxied back and gave her the beans with nearly all the right rudder I had. She lifted uneventfully and cruised off gaining steadily in altitude. A few clicks of right rudder trim and a few more of right aileron trim and she was doing great. Not fast, not slow, plenty of authority and nothing was falling off mid-flight. I tried the flaps at altitude and it was uneventful. It did not seem to produce any lift but just slow here down. I did not try the upper flaps. I took her high and did a stall test. She basically stopped flying at about walking speed (ground speed) and nosed down. No wing drop. I throttled up and got a few more passes testing WOT and lower speed passes to get a feel for her. The rudder seems to give good authority and the elevator is just a touch sensitive. I think next time I'll fly her on mid-rates to dial that elevator back a bit. My 60% expo is my go-to for maidens to keep the shaky thumbs to a minimum. While I was not nervous at all, it does help to prevent over-correction as well. I brought her around giving a good straight line up with the runway and throttled back in my final turn. She did not want to slow down much on the final approach so I throttled up and went around again. This time I throttled back at the beginning of my final turn and she slowed much better. While I did use nearly the entire length of my 300' runway she rolled in nicely with not a single event. Back taxi and done.

Overall I am very pleased with this one. She is lightly loaded and performs predictably with an easy profile to see. No real bad habits, other than the strong left pull on takeoff. I'll trim the tail wheel to bias this tendency. I also added more screws to the plates/blocks to prevent the separation observed at the field. This is a stop-gap for now as I will now pursue retracts for her. Our field is in VERY rough shape right now from all of winter and it needs to be rolled BADLY but the robustness will be fine, I think. Old MD farmland can be very unforgiving on landing gear, especially retractable ones.
 
willsonman

willsonman

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Too true! I've seen it happen far too often to NOT appreciate all parts coming down with the aircraft. I'm really digging my new approach to battery hatches for these conversions. I was so apprehensive about doing them in the past but the work far outweighs the hassle of doing it. Two hinges and a magnet are all you need. I do recommend the additional formers when needed.
 
wilmracer

wilmracer

I build things that fly (sometimes)
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Grifflyer said:
Congratulations on the maiden but...Ummm....Where's the video?:p
Click to expand...

Had the gear failure not occurred on Saturday I would have shot some, but alas. If you're really desperate I could upload 30 seconds of taxing ending with a broken mount, but that isn't all that exciting :black_eyed:

Having seen her in person she is a great looking bird. We'll get some video before too long. If Joshua brings her to SEFF we'll definitely get footage there. Otherwise I expect to be doing a lot more flying with these guys in the coming months and we'll shoot some ASAP.
 
willsonman

willsonman

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A little teaser update on this one. I've ordered retracts gear for this one and it should be arriving in the mail today. I'll be leaving for SEFF this week so I will be getting on this one again when I return.
 
willsonman

willsonman

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They arrived and I have to say I'm glad I took the time to select the proper retracts.

These are just huge but they are supporting a 13 pound airplane over some really rough field. Cast aluminum and should fit the bill nicely.
IMG_6161.JPG


I'll have to trim the aluminum just a bit but its not a huge deal. Mostly, I'm just happy to see something of this kind of quality for such a cheap price. At $30 each it is a worthwhile investment.
IMG_6162.JPG
 
wilmracer

wilmracer

I build things that fly (sometimes)
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Those should do nicely! Pretty sure I have a set of the 90* that are basically the same. They are SOLID and work great. They were just too deep to fit in the T-38's slim wing. No problems there with the Dauntless
 
rockyboy

rockyboy

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Which retracts are those? I'm in the market for a similar sized set at the moment, and like the idea of $30 each instead of $300

Thanks!
 
willsonman

willsonman

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That link is correct. The one thing I did notice upon opening one retract is that the hex bolts may need to be tightened just a bit. There was a slight amount of play between the two halves of the case. Minor but I always check out my gear whether from HK or Tower. I believe they have a 90-degree option as well.

I'll also note that the selection of oleos with 6mm holes is VERY limited. I've opted to drill out a set that I have. They were from the Bugatti project and I needed wheel offset there. Here, the plan is to enlarge the 5mm hole to 6mm to mount to the retract and the axle pin will be bent slightly (about 5 degrees) to get the wheel angle right. Since the oleos are on the inside of the wheels, I will likely need to remove the wheel well liners to make things fit better. Fine by me as I think they are rather ugly.
 
Joker 53150

Joker 53150

Mmmmmmm, balsa.
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Those retracts should be well worth the weight penalty. Nothing breaks the look of a scale flight like gear being down the entire time. I've got a Great Planes Zero with fixed gear that would look SOOOOOO much better with gear up. Maybe one day I'll do some work to make that happen.
 
willsonman

willsonman

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Agreed. The weight penalty must be paid but honestly, it will not effect this one much. There is SOOOOOO much wing on this one. I just need more stick time to familiarize myself with her.
 
Joker 53150

Joker 53150

Mmmmmmm, balsa.
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I may have missed that detail, but are you powering all the servos directly from the ESC? You'll potentially be drawing a lot of power with retracts, flaps, etc. so I assume you've considered running a separate circuit.
 
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