As part of the ongoing development of the Tucano R and responding to builder request the factory has a development program to upgrade the Tucano R to an aerobatic rated air-frame. The recent testing of the wing verified that the structure will meet the requirement of +9 g at 650 kg and simply means the Tucano could with a skilled pilot loop at full gross weight...!
TUCANO WING TEST
At this builder's request the factory forwarded the first part's of the upgrade, larger gussets plates at six [6] key points. These are now incorporated into all new air-frames.
This blog is written to record the work undertaken and is standard in the new models as required.
Firewall Station 1
This blog is written to record the work undertaken and is standard in the new models as required.
Firewall Station 1
Studying the photos supplied it was decided to start by install the larger gussets at the firewall. After marking out the hole's for the rivets in the flange face the packer was trimmed to fit between the gusset and the inside face of the existing skin. The holes were then carefully match drilled through the fuselage skin and clecoed.
The main problem fitting the top gusset was access to the top flange at the current state of assembly meant there is no access to rivet. A 0.040'' aluminium angle was fabricated and riveted to the firewall allowing the gusset to be attached at the bottom of the upper longeron and then to the angle.
Station 4
The existing brackets are folded 20 x 20 angle placing the rivet line about 10 mm from the skin. Removal of these angles was of no issue but the long stems dictated that they be drilled out. The stems were drilled out with a #80 drill and while this was accomplished with the drill available it was a bit large for the available room creating poor holes.
Why?
What when wrong, simple "get their itis" driven by a looming deadline making a decision it has to be finished TO-DAY, put simply "brain fade or classic stupidity".
Its not going well, press on and only when the %#@ hits the fan that you stop, re-engage your brain but the damage is done.
STOPPED - Regrouped, acknowledged my total stupidity.
The New Tools
The cause of the problem was a number of things but the selected tools did not help. What was needed was a drill that had the smallest offset from the body to the drill center-line.
The factory uses a air right angle drill but for this number of holes its not an option. A Bosch IXO battery drill was selected as it would fit the specification with an offset adapter with the only issue begin the low rpm requiring two [2] steps off 3.5 / 4.0 mm.
New short hex drive drills were purchased to provide maximum room with minimum wobble [a problem with hex drills].
Note: The rivets selected by Flying Legend are a multi-grip and are designed to provide superior hole filling capacity.
The Repair
The holes were enlarged to 4 mm in two steps then M4 x 12 pop rivets inserted with clearance so tight the hand pop riveter had to be ground back as far as possible just to fit too expand the rivets.
The hand of Hulk Hogen was needed to do the job so it was a two fist battle but they were all expanded using small steps and a sigh of relief exhaled with the last one..!
For the record
Just to prove I did the work as part of the approval process.
 |
| Factory Installation |
The main problem fitting the top gusset was access to the top flange at the current state of assembly meant there is no access to rivet. A 0.040'' aluminium angle was fabricated and riveted to the firewall allowing the gusset to be attached at the bottom of the upper longeron and then to the angle.
Station 4
The existing brackets are folded 20 x 20 angle placing the rivet line about 10 mm from the skin. Removal of these angles was of no issue but the long stems dictated that they be drilled out. The stems were drilled out with a #80 drill and while this was accomplished with the drill available it was a bit large for the available room creating poor holes.
 |
| Factory Installation |
Why?
What when wrong, simple "get their itis" driven by a looming deadline making a decision it has to be finished TO-DAY, put simply "brain fade or classic stupidity". Its not going well, press on and only when the %#@ hits the fan that you stop, re-engage your brain but the damage is done.
STOPPED - Regrouped, acknowledged my total stupidity.
The New Tools
The cause of the problem was a number of things but the selected tools did not help. What was needed was a drill that had the smallest offset from the body to the drill center-line. The factory uses a air right angle drill but for this number of holes its not an option. A Bosch IXO battery drill was selected as it would fit the specification with an offset adapter with the only issue begin the low rpm requiring two [2] steps off 3.5 / 4.0 mm.
New short hex drive drills were purchased to provide maximum room with minimum wobble [a problem with hex drills].
Note: The rivets selected by Flying Legend are a multi-grip and are designed to provide superior hole filling capacity.
The Repair
The holes were enlarged to 4 mm in two steps then M4 x 12 pop rivets inserted with clearance so tight the hand pop riveter had to be ground back as far as possible just to fit too expand the rivets. The hand of Hulk Hogen was needed to do the job so it was a two fist battle but they were all expanded using small steps and a sigh of relief exhaled with the last one..!
 |
| For your homework write 100 x Spar straps, stop, think Spar straps, stop, think Spar straps, stop, think Spar straps, stop ....... |
For the record
Just to prove I did the work as part of the approval process.
 |
| Gusset at Station 4 |
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| Station 4 interior [a few more rivets yet] |
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| Gusset at Station 1 firewall |
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| Station 1 interior |
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