The CHAPI projects a distortion free beam of uniform intensity over ten degrees of azimuth and is effective to within 1000 ft. of touchdown.
A wireless remote control system obviates the need for long runs of control wire to distant CHAPIs. Where control wire must circle runways or control several devices, a radio modem remote system is a very cost effective alternative. Call for details.
Power Adapter: The power adapter is mounted on 2" EMT legs (not supplied) or wall mounted. A photoelectric control sensor adjusts the CHAPI’s brightness in response to ambient light conditions. Frangible floor flanges are included. ZA757 CHAPI LHA (2 lamp) Unit: The CHAPI light housing assembly (LHA) is supported by 2" EMT legs (not included). Flexible, water tight conduit and wiring (48"), frangible floor flanges and mounting hardware are provided. L867 bases and baseplates are sold separately.
The heliport approach path indicator (CHAPI) provides the pilot with a safe and accurate glide slope on final approach to the helipad. A row of CHAPI light housing assemblies (LHAs) placed perpendicular to the approach path are seen by the pilot in combinations of red, green, and white to indicate a path that is too high, too low or correctly on slope.
The CHAPI system has a filter inserted between the white and red filters of each lens to provide a 2° wide green sector that, when visible from both units, signals the proper glide slope angle of 6°. Angle deviations that are too high show one or two white lights, and those that are too low show one or two red lights.
The CHAPI uses only two LHAs and provides simplified glide slope information. The CHAPI can be configured to read white/green/red for use on heliports. The LHAs use either 2 lamps (ZA757) or 3 lamps (ZA737). The 3 lamp configuration permits normal operation with one lamp out.
Three energy styles are available:
Style A operates from a 240VAC (120V is also available), single phase, 60 Hz power supply. 120V and 50Hz are also available.
Style B is current powered and operates on 6.6 amp series circuits from an L828 constant current regulator. Lamp brightness is controlled by the output setting on the regulator.
Style C is a 48V system powered by auto batteries. This style is of particular value on remote airstrips where it would be uneconomical to bring in power lines.
CHAPIs are manufactured to meet two temperature standards: Class I for normal operation to as low as -35° C, and Class II, with lens heaters, for temperatures to -55° C.
Flight Light/ALSTOM CHAPIs have the most reliable photometrics in the industry. On a normal day a 2-lamp CHAPI unit is visible from over 10 miles out. Light distribution curves far exceed FAA requirements.
For FAA style units, a tilt-switch in each CHAPI shuts down the entire system if any unit becomes misaligned.
• Outstanding photometric performance. Pilots say they see this CHAPI before they see any competing brand.
• Four-leg design makes each light housing assembly very stable, resulting in fewer shut-downs for realignment thereby reducing maintenance and increasing airfield utilization. (EMT legs not included with domestic orders.)
• LED indicator identifies tilt switch circuit fault.
• Quartz halogen average rated lamp life is 1200 hours! Competitor's lamps rated at only 1000 hours.
• Dust proof LHA is standard. Enhances lamp life, improves photometric performance and reduces maintenance cost.
• No optical bench or special tools required for servicing. Special access doors speed lamp changes in the field.
• Off-the-shelf lamps reduce life-cycle costs.
• Circuit breaker and on/off switch in power adapter (Style A) and in each LHA (Style B) protect equipment at all times.
• Extremely reliable power adapter features WAGO terminal blocks, gas-tight ferrelled connections and Teflon wire.
• Custom configured remote control uses radio modems instead of hard wiring to control CHAPIs.
• Aiming device kit (with spirit level) simplifies setting tilt switch and azimuth angles. Lamps are adjusted to the correct glide slope angle (± 3' of arc).
• ICAO version (no tilt switch)
• International packing - four 2" EMT legs per LHA with all units and hardware double boxed.
The 'C' in CHAPI stands for 'Cramp', the name of person who invented the system 40 years ago to help train pilots returning from Vietnam. Dave Cramp was a training captain for Bristow Helicopters in Dubai, "I was tasked with training ex-Vietnam pilots we had just employed. They were all very experienced pilots, but they had problems flying in a civilian environment where they weren't being fired at. My job was to 'civilianize' them. The big problem was getting them to fly steep approaches instead of coming in very low with a big flare just before 'crashing' on to the helipad. I needed a way to get them to see and adopt a 6 degree slope. Hence the CHAPI. It was originally made of wood with a slot at the front. My next prototype was constructed out of a plastic water container. I used this for 3 years before a company in Rugby, UK offered to further develop the device. The first commercial sale was to Aberdeen Airport in Scotland in 1982 and it is still being used there today."
Tilt Switch Circuit
Powering LHA 1
Powering LHA 2
Interruptor de inclinacion (Español)
Alimentacion de la caja LHA 1 (Español)
Alimentacion de la caja LHA 2 (Español)
Tilt Switch Circuit
• Fully gasketed dust proof light housing assembly (LHA) improves performance and reduces maintenance (standard feature).
• Large lens overhang and optional heaters forward of the lenses allow continuous operation under severe arctic conditions.
• Input power: 2-Box CHAPI 1,000 VA
• Standard input voltage: 240 VAC, ±10%
• Lamps: 200 watts, 6.6 amp quartz halogen
• Rated lamp life: 1,200 hours
• Environmental operating conditions:
- Class I: +55° to -35° C (+131° to -31° F)
- Class II: +55° to -55° C (+131° to -67° F)
- Humidity: 0% to 100%
- Wind: 100 mph (161 km/hr)
• Easy to maintain and relamp
|Part Number||Part Description|
|LA-6373||Lamps: 200 W 6.6A quartz|
|15-FFF2X425||Frangible cast aluminum floor flange|
|15-201TSA||Tilt switch assembly|
|77-104FAANTD||Photo control 208-277 VAC|
|80-019035||Filter glass, red - ZA757/4|
|80-021253||Filter spring - ZA757/4|
|80-021254||Reflector assembly - ZA757/4|
|77-RH25.47||Resistor - 25 W, 0.47 ohm (lens heater Class 2 only)|
|77-W199AX-15||Relay, contactor - 30 amp DPDT, 240 VAC|
|77-777-310||Tool for WAGO terminal blocks|
|77-RTE-P21||Timer, D-O-B adjustable - 24 VAC/DC|
|77-TB20199||Photo control base|
|77-#98-6||Precision spirit level, 6"|
|Number of lamps||2||3|
|Net weight in lb.||42||55|
|Gross weight in lb.||53||75|
|Length in inches||48||48|
|Width in inches||22||32|
|Height in inches||15||15|
|Volume in cubic yd.||0.34||0.50|
Very few problems will occur with your system. However, in the case of problems, the following pointers will help you locate and correct the problems. It is assumed that all interconnect wiring is good and that tilt switches are aligned and have continuity.
|CLASS I or CLASS II|
|Lamp 'OUT'||Check lamp (if either lamp burns out, it would not shut off the other lamp).|
|PEC operation reversed
(dim in daylight)
|Check wiring of PEC to TB3 (color coded red/blk/wht).|
|CLASS II ONLY!|
|Lamp still not 'ON'||Temporarily short TB1B, R1-1 and R1-2, then R2-1 and R2-2. As each is tested, if the failed lamp turns 'ON', the heater resistor may have failed. Check for .5 ohm resistance - replace if required.|
|CLASS I or CLASS II|
|Lamps do not burn
(RTE-P21 mode light out)
|Temporarily short Power Supply TB1 T-1 and TB1 T-2 and engage CB1. If system now functions, problem is either switches or tilt switch wiring. If problem is determined to be a particular tilt switch, readjust tilt switch by going through zero and then back. DO NOT LEAVE JUMPER IN PLACE!|
|Light Box Alignment||Footers not stable. Mounting hardware is not tight. Check floor flanges, nuts on frangible couplings, bolts & nuts on light box.|