background image

Stormscope

®

 WX-500 User’s Guide

4-10

Chapter 4 – Weather Display Interpretation

Special Patterns

Randomly Scattered Discharge Points

Atmospheric instability associated with cumulus clouds, or
developing or dissipating thunderstorms could cause
randomly scattered discharge points as shown in figure 

4-9

.

Random discharge points are more likely to appear in the
strike display mode than in the cell display mode due to the
cell display mode’s clustering algorithm. If you observe
random discharge points, continue to monitor the screen for
developing clusters which indicate thunderstorm activity.

Figure 4-9. Randomly Scattered Discharge Points

R a t e

5

2 0 0 n m

S T R I K E

:

R a t e

3

2 0 0 n m

C E L L

:

Special Patterns

Cluster & Splattering Within 25 nmi

Figure 

4-10

 shows the 

360

° weather view at the 

25

 nmi range.

One moderately active thunderstorm appears as a cluster of
discharge points at 

8:30

 centered 

14

 nmi away with a splat-

tering of discharge points throughout the 

25

 nmi range.

Such splattering is due to electrical discharges within 

3

 to 

5

nmi of the aircraft and indicates that the aircraft is too close
to the thunderstorm.

Summary of Contents for Series II

Page 1: ...Model WX 500 Series II Weather Mapping Sensor User s Guide for the Stormscope Series II Weather Mapping Sensor User s Guide for the Model WX 500 Stormscope ...

Page 2: ...rate weather mapping system is manufactured by L 3 Avionics Systems Fly with Greater Confidence You now own one of the leading instruments in the world for airborne detection and mapping of thunderstorms Unlike any other product your new Stormscope sensor will enable you to make better informed thunderstorm avoidance decisions so you can fly more safely and with greater confi dence than ever befor...

Page 3: ...actual support or rela tionship whatsoever has existed which in any way affects or mitigates proprietary rights of L 3 Commu nications Avionics Systems Inc in these developments Methods and apparatus disclosed herein may be subject to U S Patents existing or applied for L 3 Communications Avionics Systems Inc reserves the right to add improve modify or withdraw functions design modifications or pr...

Page 4: ...ing an intense radar echo There are several atmospheric phenomena other than nearby thunderstorms which can cause isolated discharge points in the strike display mode Clusters of two or more discharge points in the strike display mode however do indicate thunderstorm activity when they reappear after clearing the screen Avoid the clusters and you ll avoid the thunderstorms In the cell display mode...

Page 5: ...Each MFD shows the information consistent with the capabilities of that particular display Revision Highlights This revision C of the user s guide makes the following changes Changes occurences of Goodrich Avionics Systems to L 3 Communications Avionics Systems Inc or just L 3 Avionics Systems and makes related company contact information changes On March 28 2003 Goodrich Corporation sold its Avio...

Page 6: ......

Page 7: ...Anatomy of a Thunderstorm 2 1 Stages of aThunderstorm 2 3 The WX 500 Weather Radar 2 4 Chapter 3 Operation 3 1 Introduction 3 1 Power Up 3 1 Continuous Operator Initiated SelfTest 3 1 Clear All Discharge Points 3 2 Heading Stabilization 3 2 Error Messages 3 2 Chapter 4 Weather Display Interpretation 4 1 Introduction 4 1 Radial Spread 4 2 Typical Patterns 4 3 Mapping Headings PastThunderstorms 4 6 ...

Page 8: ...s Within 200 nmi 4 5 4 5 Range Set at 200 nmi 4 6 4 6 Aircraft Progresses 100 nmi 4 7 4 7 Range Changes to 100 nmi 4 8 4 8 Aircraft Turns to AvoidThunderstorms 4 9 4 9 Randomly Scattered Discharge Points 4 10 4 10 Cluster Splattering Within 25 nmi 4 11 4 11 Discharge Points Off the Aircraft s Nose 4 12 4 12 Line of Discharge PointsWhileTaxiing 4 13 4 13 Developing Cluster Within 25 nmi 4 14 3 1 Er...

Page 9: ... an external Multi Function Display MFD that plots the location of the thunderstorms The WX 500 is a passive sensor that listens for electromag netic signals with a receiving antenna There s no transmitter and no harmful transmissions The WX 500 works as well on the ground as it does in the air thereby giving the pilot important planning information before takeoff System Description C h a p t e r ...

Page 10: ...thunderstorms Stormscope thunderstorm detection systems can correlate the electric and magnetic signatures of light ning strikes better than other systems due to their patented sense channel technology The antenna is designed to help filter out pulsed noise from sources other than atmospheric electrical discharges Functional Description Figure 1 2 and the following paragraphs describe how the majo...

Page 11: ...ll data is most useful during periods of heavy electrical discharge activity Displaying cell data during these periods allows the pilot to quickly see where the cells are without having to sift through and analyze a screen full of discharge points Strike Data Strike data is most useful during periods of light electrical activity because strike data may show the initial discharges associated with a...

Page 12: ...ischarge points automatically on the display relative to the latest aircraft heading heading stabilization when connected to a compatible heading system Performs three types of self test power up continuous and operator initiated Allows the pilot to clear discharge points using a remotely mounted clear screen button not supplied Inhibits thunderstorm processing when the communica tions transmitter...

Page 13: ...orms create electrical discharges and radiate electromagnetic signals a The convective flow of air currents warm air going up and cold air going down leads to friction between the opposing air currents and wind shear in the space between the opposing air currents The closer together the opposing air currents are the greater the shearing force of the air currents Warm Air Mass Cold Air Mass Warm Ai...

Page 14: ...nly a small percent age of discharges occurs between the clouds and the ground Cloud to ground lightning occurs when the negatively charged lower part of a cloud induces a positive charge on an object on the ground The immense charge separation finally breaks down the insulating air and a discharge occurs dumping negative charge from the cloud onto the object and the sur rounding ground d All elec...

Page 15: ... as little as 20 minutes Cumulus Stage The cumulus or beginning stage of a thunderstorm is usually precipitation free In this stage the risks to an aircraft and its occupants include strong vertical winds severe turbu lence icing and convective wind shear Mature Stage In the mature and most intense stage of a thunderstorm the water droplets within the cloud collide and combine to form rain and hai...

Page 16: ...tic signals from electrical discharges up to 200 nmi away One disadvantage of weather radar is that the cumulus stage of a thunderstorm usually precipitation free is unlikely to appear on weather radar however it generally does contain electrical discharges which will be detected by the WX 500 as a light but increasing cluster of discharge points Another disadvantage of weather radar is that due t...

Page 17: ...t The self test takes about 25 seconds to ensure that all major WX 500 functions including antenna reception memory and microprocessor functions are operating properly An error message is displayed if a fault is detected Refer to the Error Messages section later in this chapter for more information Continuous Operator Initiated Self Test The WX 500 performs a continuous self test of antenna opera ...

Page 18: ...discharge points on the display when your aircraft changes heading Normally if the WX 500 is in stalled to use the heading stabilization feature you should never have to turn heading stabilization off however a situation may occur in which the heading input appears to be invalid but no heading flag is displayed In this case you should turn heading stabilization off until the heading input is corre...

Page 19: ...R Continue without weather mapping functions See your dealer for service Error 17 Processor Fault No test strikes NF R Continue without weather mapping functions See your dealer for service if this error occurs frequently Error 18 Processor Fault Invalid test strikes NF R Continue without weather mapping functions See your dealer for service if this error occurs frequently Error 19 Processor Fault...

Page 20: ...ithout weather mapping functions See your dealer for service Error 40 Processor Fault Main processor NF R See your dealer for service if this error occurs frequently Error 41 Processor Fault DSP or main processor F Turn off the unit and see your dealer for service Error 42 Processor Fault Main processor F Turn off the unit and see your dealer for service Error 43 Invalid Request MFD NF R See your ...

Page 21: ...53 and 54 is an example of a recoverable fault Messaging errors are likely caused by excessive noise on the communication lines or an MFD communications problem These messages automati cally clear after the message is processed and therefore may appear only briefly on the MFD Nonrecoverable Faults A nonrecoverable fault allows continued operation but without the function affected by the fault The ...

Page 22: ......

Page 23: ...e thunderstorm activity when they reappear after clearing the screen Avoid the clusters and you ll avoid the thunderstorms In the cell display mode even a single discharge point may represent thunderstorm activity and should be avoided Introduction The examples in this chapter are designed to help you relate the cell or strike patterns shown on your MFD to the size and location of thunder storms t...

Page 24: ...mmon for a triangular shaped stream of discharge points to appear between the aircraft symbol and a cluster of discharge points within the range of the WX 500 A similar stream of discharge points may appear radiating away from the aircraft symbol in the direction of possible thunderstorm activity beyond the range of the WX 500 These phenomena are examples of radial spread Discharge points in radia...

Page 25: ...n be inter preted as representing three thunderstorm cells at the following azimuth and range Cluster Azimuth clock position Range 1 11 00 180 nmi 2 4 00 75 nmi 3 4 00 180 nmi Analysis of the right hand screen strike display mode yields a similar but less certain interpretation due to radial spread The screen can also tell us about the relative amount of electrical discharge activity in thundersto...

Page 26: ... 100 nmi range and therefore no longer appear on the screen Clusters 1 and 3 would again be visible if the range were returned to 200 nmi Cluster 2 is now more defined and the discharge points are larger The interpretation of cluster 2 remains the same a moderately active thunderstorm at azimuth 4 00 range 75 nmi Notice on the right hand screen strike display mode that there is less radial spread ...

Page 27: ...e points on the screen can be interpreted as one thunderstorm cell at 5 30 about 150 nmi from the aircraft and another cell at 1 00 about 100 nmi from the aircraft The cluster at 1 00 has less radial spread in the strike display mode and fewer discharge points than the cluster at 5 30 indicating a lower rate of electrical activity Both clusters must be avoided Figure 4 4 Two Clusters Within 200 nm...

Page 28: ... past several thunderstorms Range Set at 200 nmi Figure 4 5 shows the 360 weather view at the 200 nmi range Two thunderstorms appear almost as one cluster of dis charge points off the nose of the aircraft centered 180 nmi away A second cluster at 9 30 indicates a storm system containing three thunderstorms Mapping Past Storms Figure 4 5 Range Set at 200 nmi Rate 125 200nm STRIKE Rate 117 200nm CEL...

Page 29: ... its heading and progressed 100 nmi The two thunderstorms off the nose of the aircraft appear to have expanded horizontally on the screen This effect is normal anytime you get close to a storm The line of thunderstorms previously at 9 30 now appears at 8 30 Mapping Past Storms Figure 4 6 Aircraft Progresses 100 nmi Rate 127 200nm STRIKE Rate 118 200nm CELL ...

Page 30: ... the 120 weather view at the 100 nmi range The thunderstorms at 8 30 are not visible in this view but the thunderstorms off the nose of the aircraft appear in greater detail as two separate thunderstorms at 11 30 and 12 15 centered 90 nmi from the aircraft Mapping Past Storms Figure 4 7 Range Changes to 100 nmi Rate 75 CELL 100nm Rate 75 STRIKE 100nm ...

Page 31: ...short time later after the aircraft has turned to the right to avoid the thunderstorms When connected to a compatible heading system the WX 500 automatically rotates new discharge points to their correct position relative to the new heading Figure 4 8 Aircraft Turns to Avoid Thunderstorms Rate 45 CELL 100nm Rate 45 STRIKE 100nm Mapping Past Storms ...

Page 32: ...orithm If you observe random discharge points continue to monitor the screen for developing clusters which indicate thunderstorm activity Figure 4 9 Randomly Scattered Discharge Points Rate 5 200nm STRIKE Rate 3 200nm CELL Special Patterns Cluster Splattering Within 25 nmi Figure 4 10 shows the 360 weather view at the 25 nmi range One moderately active thunderstorm appears as a cluster of discharg...

Page 33: ... display modes This is true because in the cell display mode the WX 500 plots every electrical discharge detected within the 25 nmi range at the exact location detected unless the discharge is associated with a cluster of discharges in which case the discharge point is clustered with the associated discharge points You ll also notice that there are more points in the cluster of points at 8 30 in t...

Page 34: ...nts ahead of the aircraft could be caused by a strong thunderstorm just beyond the 200 nmi range Another cause might be electrical discharge signals arriving via atmospheric skip from a distant thunderstorm well beyond the WX 500 range In either case no immediate action is required Figure 4 11 Discharge Points Off the Aircraft s Nose Rate 24 200nm STRIKE Rate 16 200nm CELL Special Patterns ...

Page 35: ...ge points across the screen as shown in figure 4 12 Similar concentrations of discharge points across the screen may appear while taxiing due to electrical signals from nearby equipment such as arc welders or subway rails After passing the source of the interference clear the screen Figure 4 12 Line of Discharge Points While Taxiing Rate 45 200nm STRIKE Rate 40 200nm CELL Special Patterns ...

Page 36: ...ping thunderstorm 12 nmi from the aircraft If you see a screen such as this with a developing cluster within 25 nmi you should change course to avoid the storm and continue to monitor the Stormscope sensor information displayed on the MFD Figure 4 13 Developing Cluster Within 25 nmi Rate 14 50nm STRIKE Rate 14 50nm CELL Special Patterns ...

Page 37: ... heading stabilization Microphone inhibit line Integrity indicator Size Processor includes mounting tray and pull handle 5 6 in 14 22 cm high 2 2 in 5 59 cm wide 12 0 in 20 48 cm deep Antenna 1 00 in 2 54 cm high 3 45 in 8 76 cm wide 6 85 in 17 40 cm long Weight Processor 2 5 lb 1 13 kg Antenna 0 84 lb 0 38 kg without doubler plate Operating Altitude 55 000 ft max Specifications C h a p t e r 5 Sp...

Page 38: ... change without notice Electrical Characteristics Input voltage 11 to 32 V dc Current 0 82 A max 12 V dc 0 38 A max 28 V dc RTCA Compliance Processor Environmental DO 160C F2 BA NBM XXXXXXZ AB ABZTZAZEZXX Processor Software DO 178B Level D Antenna DO 160C F2 AC YCLM XSFXXXXXXXZXZXXE3XX TSO Compliance Processor TSO C110a Antenna TSO C110a JTSO C110a ...

Page 39: ...t Number ________________________________ Serial Number _______________________________ Mod Letter __________________________________ Firmware Version _____________________________ Antenna Model Number_______________________________ Part Number ________________________________ Serial Number _______________________________ Mod Letter __________________________________ To ensure that a new or repair...

Page 40: ...nc 5353 52nd Street S E Grand Rapids MI 49512 USA 800 253 9525 www L 3com com as Stormscope WX 500 This technical data is controlled under the Export Administration Regulations EAR and may not be exported without proper authorization by the U S Department of Commerce ...

Reviews: