Week 2

SALINA, Kan. October 29, 2010 – The leading edge clean up continued into week two. The porous panels were all dry fit and trimmed and we began electrical work and installing brackets for interior equipment.

Trimmed and fitted panels

Porous panels after trim and fit.

Equipment pallet brackets in the cargo pod.

Brackets on the belly inside the cargo pod.

Patches were applied where the pneumatic boot feed lines used to come through the leading edges of the wings and tail surfaces.

Patch applied to the leading edge.

Patch on the right inboard wing.

The entirety of the materials that would be installed were laid out and categorized.

Equipment on tables.

A majority of the installation kit.

Equipment pallet

TKS equipment pallet

The picture above is of the equipment pallet for the Caravan. The tank holds 20.8 gallons of TKS fluid. There are 5 filters, two main pumps and two windshield pumps. The side of the pallet has a sight glass with float ball to provide the crew visual confirmation of the fluid level. A ‘Minimum Dispatch’ indicator line shows the flight crew where the ball must be above to allow take off into known icing conditions. The 11.7 gallons this line indicates is enough to allow 45 minutes of operation in the High mode.

TKS pallet sight glass.

Sight glass with Minimum Dispatch quantity indicator.

Model of sight glass

Fluid Tank Sight Gauge (left hand side of cargo pod, below left lift strut)

Fluid is supplied to the panels and propeller by a positive displacement, constant volume metering pump. The two-speed pump provides two flow rates to the panels and propeller. The low speed supplies fluid for the design point of anti-icing during a maximum continuous icing condition. The high speed doubles the flow rate for removing accumulated ice or providing ice protection for more severe conditions. Flow rates are designed for this level of performance, regardless of the certification basis for the system.

Paired metering pumps

The main pumps.

The fluid that is pumped from the equipment pallet flows through the five micro filters which assure all contaminants are removed from the fluid, preventing panel blockage. From the filters the fluid flows through nylon tubing to proportioning units in the wings and tail.

Wing Proportioning unit

A proportioning unit for one of the wings.

The proportioning units divide the flow into the volumetric requirements of each panel or device supplied through the unit.

Out With the Old

SALINA, Kan. October 22, 2010 – The rest of the first week was dedicated to removal of the boots and cleaning up the leading edges. The boots themselves stripped off fairly easily but the glue residue and edge sealant was a different matter. The area needing to be cleaned was very large and we had to ensure even the smallest amount of residue was completely removed in order to allow us to prime and paint.

 Stripping edge seal

Stripped leading edge.

While the leading edges were being cleaned up, Brandon, our panel fitting expert, went to work determining what alterations needed to be made to achieve a clean fit for the TKS panels. The outer skin of the ice protection panels are manufactured with titanium, typically 0.7 to 0.9mm thick. Titanium provides excellent strength, durability, light weight, and corrosion resistance. The panel skin is perforated by laser drilling holes, 0.0025 inches in diameter, 800 per square inch. The porous area of the titanium panels is designed to cover the stagnation point travel on the appropriate leading edge over a normal operating environment. This range is typically from best rate of climb at the low end to VNO, maximum structural cruising speed. Conservative margins are added to this range.The back plate of a typical panel is manufactured with stainless steel or titanium. It is formed to create a reservoir for the ice protection fluid, allowing fluid supply to the entire porous area. a porous membrane between the outer skin and the reservoir assure even flow and distribution through the entire porous area of the panel.

A panel crosssection.

Fluid flow from laser-drilled holes.

The porous panels can be bonded or attached as a cuff over a leading edge (typical in STC installations) or built in as the leading edge. Most high performance general aviation singles and twins utilize the cuff method. Panels are bonded to the airframe with a two part, flexible adhesive. The typical panel will have from 1 to 2 fluid inlets and a single air outlet on the inner skin.

panel inner skin

Brandon carefully fits each panel and determines the exact location for all holes that need to be drilled to plumb the panels. Once fitted he will carefully trim each panel to ensure a optimal fit.

Filing holes.

Fitting the panel

N853PA – Day 1

SALINA, Kan. October 18, 2010 – N853PA arrived at CAV Aerospace’s home base, KSLN, at 10:00 PM CST. (view Flight Tracker) It was too dark out to get a good photograph of the plane in all its glory but we managed one blurry photo:

N853PA upon arrival KSLN

After a quick walk around, we got the pilot on his way back home and secured the plane for the weekend. Salina is served by Sea Port Airlines with very reasonable flights to and from Kansas City three times a day Sunday through Friday.

Getting Started
A TKS installations always begins with an external inspection of the aircraft to identify any issues that we want to note for the owner. N853PA is a 2000 Cessna 208B Grand Caravan in very good condition. It’s equipped with a 3-blade McCauley C703 prop and the 675 SHP PT6a-114A engine.The plane came to us with the cargo pod and pneumatic boots installed.

Comprehensive
The TKS system requires that plumbing be routed throughout the aircraft. The diagram below demonstrates the extent and positioning of the TKS plumbing and components.

TKS diagram for the C208B

Once our inspection was completed 853PA was defueled and moved into an installation bay where the prop was pulled and all access plates removed.

Photo of C208B with prop pulled

Underside picture of left wing with access plates removed.

We then began the process of removing the interior seats, sidewalls and floorboards. The aft bulkhead was pulled to allow access to the empenage.

Interior of N853PA with floor boards pulled.

Aft bulkhead pulled.

While the interior was being stripped the process of removing the boots from the leading edge began. This is tedious, time consuming work but has to be done carefully to ensure we have a clean surface for bonding the TKS porous panels to the surface.

Erwin removing a boot from the left wing.

Cessna Caravan TKS™ Installation – N853PA

SALINA, Kan. October 14, 2010 – This week, CAV Aerospace, Inc. is beginning the first of many single-engine turboprop Cessna Caravan TKS™ ice protection installations to be performed in its North American facilities at the Salina Aviation Service Center. We’ll blog the installation with plenty of photographs for our TKS owners, enthusiasts and those who would like an idea of what goes into a TKS installation.

The first Caravan TKS conversion will go to Superior Airways, a chartered air service based in Red Lake, Ontario, Canada at Red Lake Airport. Superior flies cargo, fishermen, hunters, firefighters, First Nations individuals, medical patients and law enforcement to and from remote communities to the north in Northwestern Canada.

Extreme Weather
The 27 First Nations communities north of Red Lake have only ice road access for a six-week period during the winter and the extreme arctic weather conditions and terrain are unforgiving. Red Lake is the northern terminal of the highway system in the region. Consequently, the flights provided year-round by Superior Airways are a crucial life preserver for area inhabitants.

“We are pleased that Superior Airways is our launch customer for these Caravan ice protection conversions,” said CAV Aerospace President Kevin Hawley. “Soon Superior Airways will join the operators of 6,000 aircraft around the world that use our proven TKS ice protection system.”

“I asked Kevin Hawley and CAV Aerospace to install its TKS Flight Into Known Icing (FIKI) ice protection system the Caravan we recently acquired for a couple reasons,” said Mike Misurka, president of Superior Airways, and an experienced arctic weather pilot.

Reliable and Proven
“Number one reason among those was they are reliable and know what they are doing. I wanted the same system that is going into new Caravans from the factory under a Service Bulletin Installation Kit. And CAV Aerospace can give me that as a Caravan TKS Repair Center,” he adds.

“We can be 200 miles from the nearest airport and you don’t know if the weather is suitable anywhere at that point.  There is no ATC and it’s all uncontrolled air space.  So, what are you going to do at 2 a.m. when you start picking up ice in flight?” he continues. “I’m a pilot myself, so I can’t put myself or my staff in a position where they don’t have an option to continue safe flight.” TKS gives Misurka peace of mind. Superior Airways also flies several Piper Navajos and a Cessna 206.

More to Come!
We’ll be posting more soon. The aircraft is scheduled to arrive tomorrow, the 15th of October, and work will begin soon after. Subscribe to this site or make this url a favorite to keep up to date on the installation as it progresses.