Welcome to the owner area of our
website. Here will be posted information that we
hope will be useful to owners and operators of
Flight Design CT aircraft.
The information posted here will
be advisory in nature, not mandatory. However,
at times, it will direct attention towards
information that is mandatory.
- October 16, 2008 - Fuel management for the CT
On the CTsw and CTLS we use several methods to determine fuel levels for proper pre-flight planning and in-flight management.
On the CTsw in Classic configuration we use the aluminum dipstick as the basic method for checking fuel, with the clear plastic sight gauges as an in-flight back up for determining fuel remaining in the tanks.
On the CTsw Advanced configuration and CTLS with the Dual Dynon glass panel we have three methods, the dipstick, the electronic fuel flow and fuel remaining gauges and the sight gauges.
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A comment we have heard was that the dipsticks are hard to read in some light conditions. While it is true that the clear anodized dipsticks can sometimes be hard to read, there are several things one can do to help in seeing the fuel. One is to rotate the dipstick quickly after dipping to get the proper reflection, two is to take a black indelible ink marker (like a Sharpie® or Marks-A-Lot®) and make a stripe down the sides of the stick to show the wetness more easily.
One common method used by general aviation pilots is to take a clean wooden stick the same length as the dipstick and use the gauge on the dipstick as a reference to the level shown on the wood.
- The clear tube sight gauges located at the wing root allow the pilot to determine fuel remaining while in flight. However, the use of auto fuel darkens the tubes and over time may render them difficult to read. In this situation, you should have the tubes replaced at the next major service interval. If they are dark enough to the point that they are unusable, you must have them replaced before further flight. This recommendation will be further clarified in revisions to the service documents.
- The fuel computer on the Dynon equipped CTsw and CTLS provide a third method of determining the fuel remaining, but require that you reset the quantity-on-board value whenever you take on fuel. This is not unlike some much larger aircraft. The reset of the level is quite simple on the D-102 EMS screen, but so simple one can forget to do it. Also, the fuel flow and fuel remaining are approximate and should be used for guidance only and you should be conservative with your in flight planning.
Pilots should always be familiar with the aircraft fuel burn per hour and fuel onboard at the beginning of the flight as a means of backing up any of the fuel gauges.
The CT series have very large fuel tanks and are not typically limited by the amount of fuel allowed in your weight and balance. Don't let the low fuel burn numbers of the Rotax engine tempt you into an unsafe situation. Thirty minutes reserve fuel is just a few gallons, but the aircraft has a capacity of 34. With the extreme range on the CTsw and CTLS the plane can outlast their pilots.
- September 22, 2008 - Ethanol Blended Fuel
An official factory Service Notification been issued today on the subject of Information on the usage of Ethanol blended fuel. It provides specific directions to follow if you are using or have used Ethanol blended fuel. Much of what is stated duplicates the earlier Ethanol notice posted here in the FDUSA Owners section but it is formalized and now has recommendations that must be followed.
The Service Notification is in a new format that is soon to be described in detail on the maintenance support page. The format may look familiar to those of you who have seen the revised Rotax notices for the 912S engines. The idea is to make it easier for an owner or repairman to make certain that a specific model of Flight Design aircraft is in compliance with the factory maintenance and airworthiness notices. It may look a little confusing at first glance, but it is really quite simple. If you own a CTsw you will only need to look at notices for the CTsw and not notices for the original CT and older CT2K.
We will be updating the older notices to the new format and removing some that are no longer needed in the near future.
- August 19, 2008 - Ethanol
Ethanol has been in the news a lot lately and, as the result of phase separation, is believed to have contributed to the failure of a fuel filter installed in a CTSW.
Ethanol absorbs water and blends well with gasoline. However, too much water will overwhelm the ethanol's ability to remain blended with the gasoline. Because ethanol mixes easier with water than gasoline, it will separate from gasoline and accumulate with the water at the lowest point of a system. The product in the tank will no longer be a homogeneous blend of ethanol and gasoline, but two layers of product; a layer of gasoline on top and an ethanol/water layer on the bottom. This is referred to as "phase separation."
At this point, the components in the lower part of the fuel system may be exposed to higher concentrations of ethanol than they were originally designed for. The engine may receive almost pure concentrations of alcohol (perhaps as high as 90%). This may lead to failure of fuel system components, vapor lock and engine stoppage.
It is believed that phase separation can occur, not only when water is accidentally introduced into the fuel system, but also when an aircraft is operated in a humid environment and is allowed to sit for long periods.
To avoid ethanol related problems, discontinue using ethanol-blended automotive fuels.
If it can't be avoided, use a concentration of no more than 5% (considered the maximum acceptable for the Rotax 912S engine). Premium grade blended fuels often contain no more than 5% ethanol. If the percentage is higher, dilute the mix by adding some 100LL to the tanks.
Additionally:
- Never let fuel sit for too long. If an airplane is going to remain idle for a long time, drain all the fuel from the aircraft through the gascolator, which is the lowest part of the system.
- Do not operate your aircraft above 10,000 ft while using ethanol blended fuel as vapor lock may occur.
- Have your mechanic check the inline fuel filter behind the instrument panel often if ethanol-blended fuel is used and the aircraft is flown infrequently. If damage is observed or suspected, replacement fuel filters may be obtained from Flight Design USA.
For comments or questions, email: airworthiness@flightdesignusa
- June 18, 2008 - Nose Gear Damper Upgrade for SW owners
On CTLS aircraft, the metal spring damper in the nose gear assembly was replaced by a polyurethane element. What it does is reduce re-bound after a drop in on the nose wheel. It also stops the nose wheel suspension from bottoming out (going clunk). It is standard on the LS and was drop tested and certified.
Flight Design is offering for free to existing CTSW in the USA the parts to complete an optional upgrade to the urethane damper as a thank you for their business and support. (It does not address a safety issue and therefore is not mandatory).
The parts may be obtained free from Flight Design USA with the owner paying for the shipping ($ 12.00 via UPS).
The owner will also be responsible for the labor costs of installation. We recommend having it done during scheduled maintenance at a Flight Design Service Center.
- June 16, 2008 - CT Firewall and Oil Hose Sleeve Upgrade.
As many of you may be aware, one of the production changes requested on newer CT's distributed in North America was the addition of a firewall blanket and oil hose sleeving in the engine compartment in order to provide additional fire protection and reduced cabin noise. These changes were implemented in late 2006. The original firewall is carbon fiber coated with fireproof epoxy resin.
We realized that retro-fitting existing aircraft was highly desirable and asked the factory to supply us with kits to perform the modifications. Subsequently, numbers of aircraft have had the upgrade performed at Flight Design Service Centers around the country.
However, it recently came to our attention that not enough aircraft have benefited from this opportunity and, more importantly, we realized that, in the interest of conformity and enhanced safety for all the planes in the country, the upgrade should be made mandatory.
Now, to answer the obvious questions:
Parts:
Flight Design will supply the parts and materials.
Labor:
The fixed cost at a Flight Design Service Center for the upgrade should be $1450.00; of which $1000.00 will be paid for by the factory and $450.00 will be charged to the aircraft owner (It will be the owners responsibility to bring their plane to the service center and back).
Where:
We strongly recommend having the modification performed at a Flight Design Service Center. There are other locations around the country that are factory trained on Rotax engines and have received documented approval from Flight Design for installing the upgrade. Flight Design will reimburse $1000.00 towards the cost once the upgrade has been completed and after proper compliance documentation has been submitted.
When:
We will soon be issuing a Safety Directive (Service Bulletin) that will require that the upgrade be performed within a year of the date of issuance. We suggest having the procedure completed during the annual or 100 hour inspection.
A couple of items of note:
The details, including cost, are subject to change pending the issuance of the Safety Directive. This Owner news item is provided for informational purposes only and should not be construed as a guarantee to provide said parts, services and remuneration at the above mentioned dollar amounts
In accordance with the ASTM standards, Flight Design does not use notices of corrective action (Safety Directives) to promote or make mandatory non-safety of flight related equipment upgrades or additions.
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