NTPS

Traffic Advisory SystemEvaluation

Morten Andersen Massimo Salciccia

Goodrich SkyWatch SKY 497Cirrus SR - 22

2 NTPS

Objective - PurposeIntroductionMethodTest ResultsConclusionRecommend.

General

• Execute a Limited Evaluation of SKY 497

• Not an approved TCAS-II system

• However similar displays / alerts

• Is it a viable system??

Specific (AC 20– 131a)

• Basic GND test (Para. 3.f.1.i-ix)

• Basic FLT test (Para. 3.f.2.i-iv, vii-viii)

• Encounter test (Para. 3.f.3.i-v)

3 NTPS

Test TeamIntroductionMethodTest ResultsConclusionRecommend.

Test Team• Safety Pilot: ED• Pilot: Morten• FTE: Massimo

Mission Representative Operators• Like most GA operators – unfamiliar with TCAS• Yes - representative

4 NTPS

MissionIntroductionMethodTest ResultsConclusionRecommend.

Expected Mission of the Aircraft• General Aviation• SGL pilot concept – possible inexperienced• Fully IFR certified• Ceiling: 13000ft MSL• Normal cruise speed: 120 – 150 KIAS

5 NTPS

Test Item DescriptionIntroductionMethodTest ResultsConclusionRecommend.

• Cirrus SR 22 (Experimental)

• TAS SKY 497

• Production representative – YES!

6 NTPS

IntroductionMethodTest ResultsConclusionRecommend.

SKY497

operation

• Track 32 AC

• Display 8 AC

• Eff. range: 8 NM

• Aural + vis.Alerts

• No RA!

7 NTPS

InstrumentationIntroductionMethodTest ResultsConclusionRecommend.

• Intruder aircraftB-76 w. GPS

• Garmin 92• Aircraft Radios

8 NTPS

Test ConditionIntroductionMethodTest ResultsConclusionRecommend.

Aircraft• Both aircraft CG and weight - STD• Minor electrical problem w. Cirrus on start up

– Considered no factor

Weather• Wind / Velocity • 240° / 13Kts• Visibility > 50 Km

9 NTPS

Assumptions - LimitationsIntroductionMethodTest ResultsConclusionRecommend.

Assumptions• SR-22 production representative• Garmin 92 provides truth Data

Limitations• Only 1.5 Hrs Flight Evaluation

– Extensive test points req. to show compliance on a standard percentile confidence level

– Not possible – striving for a sound estimate• Only Day light evaluation

10 NTPS

Test ChronologyIntroductionMethodTest ResultsConclusionRecommend.

Test assignment 16th February 2005

Data Card Review 21st February 2005

Flight Test TAS 24th February 2005

Oral Report 25th February 2005

11 NTPS

Test MethodIntroductionMethodTest ResultsConclusionRecommend.

Ground Test Self Test Bearing Accuracy Test: +/- 15 deg

Observe wingman squawk on GND Sensor Failure

Pull CB’s

Electromagnetic Interference (EMI) Observe all instruments

Evaluate Controls & Display General impression

12 NTPS

Test MethodIntroductionMethodTest ResultsConclusionRecommend.

Basic Flight Test Interference with other Aircraft Systems

Observe VOR/GPS/Radios Aural Messages

Present / non-present Acceptable Volume and Intelligibility

With and without headset Confirm Valid & Usable traffic info during

maneuver ± 15° of pitch & ± 30° of Bank

Surveillance Range Traffic info out to 11NM

13 NTPS

Test MethodIntroductionMethodTest ResultsConclusionRecommend.

Planned Encounter Flight Test 2 x Head-on Test

Low & High Speed 2 x Crossing Test (90 deg) 2 x Converging Test

(45 – 60 deg) 1 x Overtaking Traffic

Method: Cirrus calls “Mark” Lat/Long/Baro/Track/GS

recorded

14 NTPS

Test MethodIntroductionMethodTest ResultsConclusionRecommend.

Subjective Rating Scale TAS improve your S.A with respect to other traffic? TAS display is easily read and easily distinguished? TAS controls are easy to use?

21 6543

DisagreeStrongly Disagree

Moderately Disagree

Moderately Agree

Agree Strongly Agree

NTPS

Test Results

16 NTPS

Ground TestIntroductionMethodTest ResultsConclusionRecommend.

Self Test Very satisfactory – expeditious test!

Bearing Accuracy Test: req. +/- 15 deg High confidence in accuracy Short range… Satisfactory

Sensor Failure – Pull CB’s System CB pulled – immediately “Fail” Satisfactory

Electromagnetic Interference (EMI) None observed Satisfactory

17 NTPS

Ground TestIntroductionMethodTest ResultsConclusionRecommend.

Evaluate Controls & DisplayDual Controls / Displays

Garmin 430: Too small a display Cumbersome controls

Avidyne: Good overview Easy to see display Full control

Overall: Very Satisfactory

18 NTPS

Flight TestIntroductionMethodTest ResultsConclusionRecommend.

Basic Flight Test Interference with other Aircraft Systems

Possible interference observed on Storm Scope Frequent Lightning Alert (RNG 200NM!) Unknown cause [R-2]

Aural Messages Only “Traffic, Traffic” in system Apparently worked per intention Satisfactory

Acceptable Volume and Intelligibility Easy to hear, with and without Headphones. Satisfactory

19 NTPS

Flight TestIntroductionMethodTest ResultsConclusionRecommend.

Basic Flight Test Valid & Usable traffic info during maneuvers

± 15° of pitch & ± 30° of Bank w. intruder Accuracy assessed accurate to within 15 deg

Track only observed lost twice during entire test Reacquired within ~5 seconds Satisfactory

Surveillance Range System spec: Traffic info out to 11NM Intruder and other traffic displayed at 11 NM Satisfactory

20 NTPS

Flight Test – Planned EncounterIntroductionMethodTest ResultsConclusionRecommend.

Head On Encounter

• 8 seconds too late – non compliance?• Maybe… maybe not!• Only one datapoint [R-1]

SR-22GS

B-76GS

Ang.Closure

Cal.Alert

Range

RealAlert

RangeDiff.

ErrorBudget

Time out ofSpec.

160kt 135kt 287kt 14530’ 9175’ 5355’ 1575’ 8 sec.

120kt 100kt 212kt 10735’ 10730’ 5’ Pass

TRK X-ING ANGLE

165° / 195°

21 NTPS

Flight Test – Planned EncounterIntroductionMethodTest ResultsConclusionRecommend.

Crossing Encounter

• Satisfactory!

SR-22GS

B-76GS

Ang.Closure

Cal.Alert

Range

RealAlert

RangeDiff.

ErrorBudget

Time out ofSpec.

150kt 130kt 215kt 10885’ 10585’ 300’ 1200’ Pass

TRK X-INGANGLE

100°

22 NTPS

Flight Test – Planned EncounterIntroductionMethodTest ResultsConclusionRecommend.

Converting Encounter

• Satisfactory!

SR-22GS

B-76GS

Ang.Closure

Cal.Alert

Range

RealAlert

RangeDiff.

ErrorBudget

Time out ofSpec.

127kt 130kt 117kt 5925’ 5550’ 375’ 700’ Pass

TRK X-INGANGLE

63°

23 NTPS

Flight Test – Planned EncounterIntroductionMethodTest ResultsConclusionRecommend.

Overtaking Encounter

• Satisfactory!

SR-22GS

B-76GS

Ang.Closure

Cal.Alert

Range

RealAlert

RangeDiff.

ErrorBudget

Time out ofSpec.

97kt 156kt 61kt 3040’ 2900’ 140’ 425’ Pass

TRK X-ING ANGLE

016°

24 NTPS

Test MethodIntroductionMethodTest ResultsConclusionRecommend.

Subjective Rating Scale TAS improve your S.A with respect to other traffic? TAS display is easily read and easily distinguished? TAS controls are easy to use?

21 6543

DisagreeStrongly Disagree

Moderately Disagree

Moderately Agree

Agree Strongly Agree

25 NTPS

ConclusionsIntroductionMethodTest ResultsConclusionRecommend.

Displays / Functionality / Usability• System is very easy to use• System gives good and instant SA on factor traffic• System seems consistent• Acceptable use of visual and auditory alerts• Possible interference with StormScope – should be

investigated [R-2]

26 NTPS

ConclusionsIntroductionMethodTest ResultsConclusionRecommend.

Specifications• All but one test run showed compliant values• High speed Head On Encounter failed.• Too many uncertainties to fail the system on one

test point. [R-1] • Generally – high confidence in system

27 NTPS

Overall ConclusionsIntroductionMethodTest ResultsConclusionRecommend.

The SKY 497 is estimated to be a

Viable and Usable

Traffic Alerting System in the role of

General Aviation

28 NTPS

RecommendationsIntroductionMethodTest ResultsConclusionRecommend.

[R-1] The High Speed Head On Encounter alerting function of the SKY 497 should be evaluated under further flight test.

[R-2] The SKY 497 should be investigated for possible interference with the Storm Scope system.

29 NTPS

Questions

30 NTPS

Error Budgets

• GDOP of 4: 60ft• 2 seconds time delay in Mark

– Gives error budget along angular closure vector

– For two aircraft!• 1 second update rate for GPS

– Gives error budget along angular closure vector

– For two aircraft

31 NTPS

Assignment