wahrhaftig
May 01, 1996, 01:00 AM
<html>
<head>
<title>A Review of the ACE Tiger Kitten Electric</title>
</head>
<body bgcolor="#FFFFFF">
<p align="center"><img src="http://static.rcgroups.com/articles/ezonemag/1996/../images/tig2.jpg" width="365" height="262"> </p>
<p><strong>Introduction:</strong></p>
<p>When I first saw the Tigerkitten "E" as published by Bob Benjamin in Model
Aviation, September 1991, it was love at first sight. First there was the appeal of its
looks, a graceful 1930's-style low wing monoplane with open cockpit and big streamlined
wheel pants. That's my kind of airplane, all right. Then there was the quality of its
engineering. Here was a plane specifically designed for electric by someone who obviously
knew what he was doing. Nowhere is there a mite of excess structure, unnecessarily heavily
material, or artless structure. Also, the many photos were dynamite, clearly showing
important features of the design and showcasing a quality of craftsmanship that I envied,
and still envy. I sent away for plans, but never built the 'kitten at that time because I
had seven cell battery packs and a seven cell charger and wasn't ready to invest in
equipment for the nine cell packs that Benjamin recommends for an Astro cobalt .05. Now
ACE R/C has kitted the design, I have taken the plunge and built it, and our story can
continue.</p>
<p>Even if you decide to build the kit, I recommend that you obtain the original
construction article, if possible. Dispensing with specific instructions on how to build
the plane (these are supplied with the plans), the article is instead crammed with
information on the philosophy underlying this design and a lengthy discussion of
appropriate equipment - batteries, speed controls, connectors, propellers, and so forth.
Also, you can see two versions (Astro .05 and Astro .15 powered) of the Tigerkitten flying
in promotional videotapes issued by AstroFlite. The video convincingly demonstrates the
aerobatic capacities of this design Your local hobby dealer may be able to lend you a
copy. Mine did. </p>
<p><strong>The design:</strong></p>
<p>We are talking about a 54" wingspan, 450 square inch beauty which will weigh 50 to
65 ounces depending on hardware and builder skill. This airplane has been designed for a
geared Astro cobalt .05 and 9 cells or a geared Astro cobalt .15 and 12 cells. To this ACE
has added instructions and motor mount material for a MEC Turbo 10.</p>
<p>The design is unusual in several respects. The Tigerkitten kit is available in electric
or glow versions. Unlike many contemporary electric kits which are conversions from glow
designs, the glow version of the Tigerkitten was derived from the electric. Modifications
for .25 glow largely consist of substitution of hardwood or ply for balsa in critical
places. Glow instructions are added in italic type to the original electric instruction
manual and are obvious paste-on added to the original electric plans.</p>
<p>Accessibility has obviously been an important design consideration. Removing the cowl
exposes the motor and motor mount for inspection and adjustment. A hatch, retained by one
spring loaded latch, runs from the firewall to the rear of the cockpit, making battery
pack changes quick and easy.</p>
<p>Most of us know that in a crash, our heavy battery packs thrust forward, obliterating
everything in their path, and often what is obliterated is an expensive radio receiver (do
your really want to know how I know that?.....nahhh). Something I particularly like about
the 'kitten is that a 1/16 ply deck runs from the firewall to the rear of the cockpit,
supported by longitudinal rails and retained by wood screws. The battery packs are mounted
on top of this deck, and the radio switch, arming switch, and charging jack protrude
upwards through it at the rear where they may be easily reached through the cockpit. The
receiver, speed control and receiver battery are all mounted to the underside of this deck
where they are protected from flying battery packs. They can be reached for servicing by
removing the wing, or the entire deck with all equipment can be unscrewed and lifted out.
Fine idea! </p>
<p><strong>The kit:</strong></p>
<p>To begin with, this is an excellent kit. My local hobby dealer hates ACE kits because
the parts are protected by shredded scrap paper - lots of it - which loves to jump out and
mess up the floor no matter how carefully you open the box. Friend dealer would rather you
just took the kit home and looked at it there. ACE rather defensively puts in a slip of
paper pointing out that putting this waste paper to good use is ecologically sound. Well,
OK: nuff said about that.</p>
<p>Within, you will find excellent and consistently light materials and a very complete
array of hardware. Many parts are laser cut while others are cleanly die cut. There are
well drawn plans,a 16 page instruction book illustrated with both photos and drawings, and
enough decals to provide two or three choices of color for each. With two exceptions, I
was satisfied with the kit material and felt no need to replace any of it. In the original
Tigerkitten design published in Model Aviation, the ailerons are built up. In the kit,
solid ailerons a full 1/2 inch thick are supplied. Although the wood is light, I see no
need to haul such hefty chunks through the sky. My solution was to drill a series of wide
holes and cut out the material between pairs of holes. This produces the near equivalent
of a built up aileron and, additionally, looks rather pretty under transparent covering.
Where the original plan shows a rather graceful landing gear of .090 aluminum, the kit
supplies a broad and hefty gear of 1/8 aluminum. I don't like the idea of hauling that
much metal around and was sorely tempted to get out my drill and apply the good old swiss
cheese approach, but on the advice of people who answered my query about this on an e-mail
conference I refrained. I suspect you might want this much gear if you are going to use 12
cells, but I'm not convinced it is necessary for the 9 cell version. If you feel a need to
shave weight, here is a place to start.</p>
<p align="center"><img src="http://static.rcgroups.com/articles/ezonemag/1996/../images/tig1.jpg" width="224" height="233"></p>
<p><strong>Construction:</strong></p>
<p>Be prepared to spend some time building this kit. All flight surfaces are built up and
the fuselage is an assembly of 3/16 sticks. No special tools or techniques are required,
but this is nevertheless a builder's model. There are, of course, very adequate
construction instructions in the kit. I intend to do no more than note a few tips about
things that are not obvious from the plans and booklet.</p>
<p>Wing tips and tail tips. </p>
<p>The tips of all flight surfaces are constructed free flight style by laminating four
layers of 1/16 balsa around a form. I thought supplying die cut forms with the kit would
have been a nice touch, but here you are left to your own devices. The instructions
suggest that you could stick a bunch of pins in the plan and laminate around them, but
this I would discourage. The result is bound to be lumpy. What I do suggest is that you
cut strips of 1/64 ply off the scrap edges of the supplied die cut sheet and glue these to
the edge of cardboard forms. This will provide a smooth clean edge which you can then wax
by rubbing with an old candle in order to produce smoothly curved tips.</p>
<p>Wing:</p>
<p>If the part of building I like least is building wings, the part of building wings I
like least is installing webbing. Guess what? The Tigerkitten has webbing the full length
of the wing on both sides of the spars. Oh well, that's where the wing's strength plus
lightness comes from, so live with it. </p>
<p>The Model Aviation article stresses the importance of strengthening the wing by
notching the wing ribs into the trailing edge. In the kit, this is rather inconspicuously
shown on the plans, but is not mentioned in the construction booklet. Do it!</p>
<p>A step that is specified but is easy to overlook is adding 1/16 strips along the length
of the trailing edge on both top and bottom. This not only thickens and strengthens the
trailing edge but also allows the rib capstrips to join flush with both the trailing edge
and the leading edge sheeting. </p>
<p>Fuselage:</p>
<p>There's lots to do here, but nothing very mysterious. Like the trailing edge, the
fuselage longerons receive a lengthwise 1/16 strip which extends from the aft edge of the
forward fuselage sheeting to the aft end of the fuselage. Don't miss adding this.</p>
<p>The construction book says to drill the plate which will be tapped to receive the wing
mounting bolt with a 11/64th drill. I think the correct size is 13/64.</p>
<p>Hatch: </p>
<p>The hatch which forms the fuselage top from the firewall to the rear of the cockpit is
formed of 1/16 balsa formed over a structure of formers and stringers.</p>
<p>If used as is, the front former will block two air cooling holes which are laser cut
into the firewall, and the former is not strong enough to withstand removing this
material. My solution was to use thin CA to bond scrap fiberglass (from the strip supplied
for joining the wheel pant halves) to the back of the former before assembly. Once the
hatch is assembled, material can be cut away easily by using a sanding drum on a Dremel
tool or equivalent. Be careful not to trim the hatch sheeting flush with the front of the </p>
<p>front hatch former. This sheeting should protrude over the top of the firewall. The
best idea is to install the completed hatch and then sand the sheeting flush with the
firewall.</p>
<p align="center"><img src="http://static.rcgroups.com/articles/ezonemag/1996/../images/tig3.jpg" width="358" height="256"></p>
<p><strong>Flying:</strong></p>
<p>Watch the Astro Flight video and you'll be convinced. As for me, I am still feeling out
my Tigerkitten. After only five flights what I can tell you at this point is that this
airplane is stable and easy to fly. Using an Astro cobalt geared .05, a Master Airscrew
11/9 electric prop, and 9 1400 miliamp SCR cells, mine takes off quickly and climbs to
cruise altitude as fast as my .40 glow powered Spitfire - in fact my impression is that it
gains altitude somewhat faster. At full throttle, the Tigerkitten is very responsive, but
at low throttle it turns out to be a floater. Not only will it loaf along, on one lifty
day it clearly wanted to exercise its talents as a thermal flier. </p>
<p>My only problem has been with duration. Using an Astro Flight Model 215 Micro-speed
control and Astro connecters, my power on duration is only 3 1/2 minutes. I do not think
this is the Tigerkitten's fault because I have had similar results with previous planes. I
bring the matter up in hopes readers of this review will give me advice for improving
flight duration.</p>
<p>Albert Wahrhaftig<br>
<a href="http://rcgroups.com/shared/nospam.php?u=albert.wahrhaftig&d=sonoma.edu">albert.wahrhaftig(at)sonoma.edu</a></p>
<p align="center"><strong><img src="http://static.rcgroups.com/articles/ezonemag/1996/../images/wahr2.jpg" width="336" height="206"><br>
A picture of the author with his Tigerkitten and other aircraft.</strong>
</body>
</html>
<head>
<title>A Review of the ACE Tiger Kitten Electric</title>
</head>
<body bgcolor="#FFFFFF">
<p align="center"><img src="http://static.rcgroups.com/articles/ezonemag/1996/../images/tig2.jpg" width="365" height="262"> </p>
<p><strong>Introduction:</strong></p>
<p>When I first saw the Tigerkitten "E" as published by Bob Benjamin in Model
Aviation, September 1991, it was love at first sight. First there was the appeal of its
looks, a graceful 1930's-style low wing monoplane with open cockpit and big streamlined
wheel pants. That's my kind of airplane, all right. Then there was the quality of its
engineering. Here was a plane specifically designed for electric by someone who obviously
knew what he was doing. Nowhere is there a mite of excess structure, unnecessarily heavily
material, or artless structure. Also, the many photos were dynamite, clearly showing
important features of the design and showcasing a quality of craftsmanship that I envied,
and still envy. I sent away for plans, but never built the 'kitten at that time because I
had seven cell battery packs and a seven cell charger and wasn't ready to invest in
equipment for the nine cell packs that Benjamin recommends for an Astro cobalt .05. Now
ACE R/C has kitted the design, I have taken the plunge and built it, and our story can
continue.</p>
<p>Even if you decide to build the kit, I recommend that you obtain the original
construction article, if possible. Dispensing with specific instructions on how to build
the plane (these are supplied with the plans), the article is instead crammed with
information on the philosophy underlying this design and a lengthy discussion of
appropriate equipment - batteries, speed controls, connectors, propellers, and so forth.
Also, you can see two versions (Astro .05 and Astro .15 powered) of the Tigerkitten flying
in promotional videotapes issued by AstroFlite. The video convincingly demonstrates the
aerobatic capacities of this design Your local hobby dealer may be able to lend you a
copy. Mine did. </p>
<p><strong>The design:</strong></p>
<p>We are talking about a 54" wingspan, 450 square inch beauty which will weigh 50 to
65 ounces depending on hardware and builder skill. This airplane has been designed for a
geared Astro cobalt .05 and 9 cells or a geared Astro cobalt .15 and 12 cells. To this ACE
has added instructions and motor mount material for a MEC Turbo 10.</p>
<p>The design is unusual in several respects. The Tigerkitten kit is available in electric
or glow versions. Unlike many contemporary electric kits which are conversions from glow
designs, the glow version of the Tigerkitten was derived from the electric. Modifications
for .25 glow largely consist of substitution of hardwood or ply for balsa in critical
places. Glow instructions are added in italic type to the original electric instruction
manual and are obvious paste-on added to the original electric plans.</p>
<p>Accessibility has obviously been an important design consideration. Removing the cowl
exposes the motor and motor mount for inspection and adjustment. A hatch, retained by one
spring loaded latch, runs from the firewall to the rear of the cockpit, making battery
pack changes quick and easy.</p>
<p>Most of us know that in a crash, our heavy battery packs thrust forward, obliterating
everything in their path, and often what is obliterated is an expensive radio receiver (do
your really want to know how I know that?.....nahhh). Something I particularly like about
the 'kitten is that a 1/16 ply deck runs from the firewall to the rear of the cockpit,
supported by longitudinal rails and retained by wood screws. The battery packs are mounted
on top of this deck, and the radio switch, arming switch, and charging jack protrude
upwards through it at the rear where they may be easily reached through the cockpit. The
receiver, speed control and receiver battery are all mounted to the underside of this deck
where they are protected from flying battery packs. They can be reached for servicing by
removing the wing, or the entire deck with all equipment can be unscrewed and lifted out.
Fine idea! </p>
<p><strong>The kit:</strong></p>
<p>To begin with, this is an excellent kit. My local hobby dealer hates ACE kits because
the parts are protected by shredded scrap paper - lots of it - which loves to jump out and
mess up the floor no matter how carefully you open the box. Friend dealer would rather you
just took the kit home and looked at it there. ACE rather defensively puts in a slip of
paper pointing out that putting this waste paper to good use is ecologically sound. Well,
OK: nuff said about that.</p>
<p>Within, you will find excellent and consistently light materials and a very complete
array of hardware. Many parts are laser cut while others are cleanly die cut. There are
well drawn plans,a 16 page instruction book illustrated with both photos and drawings, and
enough decals to provide two or three choices of color for each. With two exceptions, I
was satisfied with the kit material and felt no need to replace any of it. In the original
Tigerkitten design published in Model Aviation, the ailerons are built up. In the kit,
solid ailerons a full 1/2 inch thick are supplied. Although the wood is light, I see no
need to haul such hefty chunks through the sky. My solution was to drill a series of wide
holes and cut out the material between pairs of holes. This produces the near equivalent
of a built up aileron and, additionally, looks rather pretty under transparent covering.
Where the original plan shows a rather graceful landing gear of .090 aluminum, the kit
supplies a broad and hefty gear of 1/8 aluminum. I don't like the idea of hauling that
much metal around and was sorely tempted to get out my drill and apply the good old swiss
cheese approach, but on the advice of people who answered my query about this on an e-mail
conference I refrained. I suspect you might want this much gear if you are going to use 12
cells, but I'm not convinced it is necessary for the 9 cell version. If you feel a need to
shave weight, here is a place to start.</p>
<p align="center"><img src="http://static.rcgroups.com/articles/ezonemag/1996/../images/tig1.jpg" width="224" height="233"></p>
<p><strong>Construction:</strong></p>
<p>Be prepared to spend some time building this kit. All flight surfaces are built up and
the fuselage is an assembly of 3/16 sticks. No special tools or techniques are required,
but this is nevertheless a builder's model. There are, of course, very adequate
construction instructions in the kit. I intend to do no more than note a few tips about
things that are not obvious from the plans and booklet.</p>
<p>Wing tips and tail tips. </p>
<p>The tips of all flight surfaces are constructed free flight style by laminating four
layers of 1/16 balsa around a form. I thought supplying die cut forms with the kit would
have been a nice touch, but here you are left to your own devices. The instructions
suggest that you could stick a bunch of pins in the plan and laminate around them, but
this I would discourage. The result is bound to be lumpy. What I do suggest is that you
cut strips of 1/64 ply off the scrap edges of the supplied die cut sheet and glue these to
the edge of cardboard forms. This will provide a smooth clean edge which you can then wax
by rubbing with an old candle in order to produce smoothly curved tips.</p>
<p>Wing:</p>
<p>If the part of building I like least is building wings, the part of building wings I
like least is installing webbing. Guess what? The Tigerkitten has webbing the full length
of the wing on both sides of the spars. Oh well, that's where the wing's strength plus
lightness comes from, so live with it. </p>
<p>The Model Aviation article stresses the importance of strengthening the wing by
notching the wing ribs into the trailing edge. In the kit, this is rather inconspicuously
shown on the plans, but is not mentioned in the construction booklet. Do it!</p>
<p>A step that is specified but is easy to overlook is adding 1/16 strips along the length
of the trailing edge on both top and bottom. This not only thickens and strengthens the
trailing edge but also allows the rib capstrips to join flush with both the trailing edge
and the leading edge sheeting. </p>
<p>Fuselage:</p>
<p>There's lots to do here, but nothing very mysterious. Like the trailing edge, the
fuselage longerons receive a lengthwise 1/16 strip which extends from the aft edge of the
forward fuselage sheeting to the aft end of the fuselage. Don't miss adding this.</p>
<p>The construction book says to drill the plate which will be tapped to receive the wing
mounting bolt with a 11/64th drill. I think the correct size is 13/64.</p>
<p>Hatch: </p>
<p>The hatch which forms the fuselage top from the firewall to the rear of the cockpit is
formed of 1/16 balsa formed over a structure of formers and stringers.</p>
<p>If used as is, the front former will block two air cooling holes which are laser cut
into the firewall, and the former is not strong enough to withstand removing this
material. My solution was to use thin CA to bond scrap fiberglass (from the strip supplied
for joining the wheel pant halves) to the back of the former before assembly. Once the
hatch is assembled, material can be cut away easily by using a sanding drum on a Dremel
tool or equivalent. Be careful not to trim the hatch sheeting flush with the front of the </p>
<p>front hatch former. This sheeting should protrude over the top of the firewall. The
best idea is to install the completed hatch and then sand the sheeting flush with the
firewall.</p>
<p align="center"><img src="http://static.rcgroups.com/articles/ezonemag/1996/../images/tig3.jpg" width="358" height="256"></p>
<p><strong>Flying:</strong></p>
<p>Watch the Astro Flight video and you'll be convinced. As for me, I am still feeling out
my Tigerkitten. After only five flights what I can tell you at this point is that this
airplane is stable and easy to fly. Using an Astro cobalt geared .05, a Master Airscrew
11/9 electric prop, and 9 1400 miliamp SCR cells, mine takes off quickly and climbs to
cruise altitude as fast as my .40 glow powered Spitfire - in fact my impression is that it
gains altitude somewhat faster. At full throttle, the Tigerkitten is very responsive, but
at low throttle it turns out to be a floater. Not only will it loaf along, on one lifty
day it clearly wanted to exercise its talents as a thermal flier. </p>
<p>My only problem has been with duration. Using an Astro Flight Model 215 Micro-speed
control and Astro connecters, my power on duration is only 3 1/2 minutes. I do not think
this is the Tigerkitten's fault because I have had similar results with previous planes. I
bring the matter up in hopes readers of this review will give me advice for improving
flight duration.</p>
<p>Albert Wahrhaftig<br>
<a href="http://rcgroups.com/shared/nospam.php?u=albert.wahrhaftig&d=sonoma.edu">albert.wahrhaftig(at)sonoma.edu</a></p>
<p align="center"><strong><img src="http://static.rcgroups.com/articles/ezonemag/1996/../images/wahr2.jpg" width="336" height="206"><br>
A picture of the author with his Tigerkitten and other aircraft.</strong>
</body>
</html>