Devices Major Michael Luby Aerospace Physiologist RAF Centre Of - - PowerPoint PPT Presentation

A Comparison Of Custom Molded Versus Foam In Ear Communication Devices

Major Michael Luby Aerospace Physiologist RAF Centre Of Aviation Medicine

RAF Centre of Aviation Medicine

Problem

• Changes In EU Legislation
• Subsequent Change In UK Law
• Modern Jet Fighters Can Exceed 130 Db
• 100 dB In The Cockpit
• Current Protection Equipment Does Not

Meet Need

• What Type Of Ear Plug Is Perceived As More

Comfortable And Functional

RAF Centre of Aviation Medicine

Task

• RAF CAM Tasked By S&AD IPT (Jun 06)

– Comparative & Quantitative Assessment Of COTS IECDs – Precursor To Aircraft Integration/Formal Procurement – Provide Aeromedical Advice – Provide Ranked List

• Products selected by S&AD IPT

RAF Centre of Aviation Medicine

Scope Of Trial

• Ground Trial

– Comfort – Donning and Doffing – Cleaning – Altitude Chamber

• Flight Trial

– In-flight Comfort – Communication Quality

RAF Centre of Aviation Medicine

Bias

• Custom Molded Tried First
• Subjects Could Talk To Each Other
• Subjects Past Experience With Ear Plugs

RAF Centre of Aviation Medicine

Assumptions

• Products Built To Specs
• Participants Were Truthful In Reporting

Ground Trial

– 5 Systems

A B C E D

RAF Centre of Aviation Medicine

Ground Trial

• 6 Subjects

– 2 Pilots – 2 Medical Officers – 1 Aerospace Physiologist – 2 Survival Equipment Specialists

• Methodology

– Subjects Wore System In Office Environment – 1 Hour Minimum Per Session – Used System For Minimum Of 2 Weeks – Subjects Logged Each Session – Questionnaire Following Use

RAF Centre of Aviation Medicine

Results

• Subjects Rated IECD As

– Fully Acceptable (2) – Acceptable (1) – Barely Acceptable (-1) – Unacceptable (-2)

• Average Obtained And Plotted In Chart

Results

A A A B B B C C C D D D E E E Avg Avg Avg

• 2
• 1

1 2 How easy is it to insert the earplugs? How easy is it to don the helmet with the earplugs in place? Ability to adjust earplugs once the helmet is on Helmet Interations

Results

A A A A B B B B C C C C D D D D E E E E Avg Avg Avg Avg

• 2
• 1

1 2 Please assess your comfort rating wearing the earplug without a helmet? Please assess your comfort rating wearing the earplug with a helmet? How easy is it to insert the earplugs? How easy is it to don the helmet with the earplugs in place? Comfort

RAF Centre of Aviation Medicine

Results

• Custom Moulded Found To Be More

Comfortable

• All Systems Vented Without Problems
• IECD “D” Rejected

– Too Bulky – Silicone Splitting

• IECD “E” Rejected

– Air Tubes Conducted Too Much Noise

RAF Centre of Aviation Medicine

Flight Trial

• Remaining Systems

Carried Over To Flight Trial In RAF CAM Hawk

• Subjects

– 3 Pilots – 1 Medical Officer – 1 Aerospace Physiologist

RAF Centre of Aviation Medicine

Flight Trial

• Methodology

– 1 Flight Per System Per Subject

• Subjects Completed Questionnaire Following

Flight

– Satisfactory (1) – Unsatisfactory (0) – Unacceptable (-1)

• Average Obtained And Plotted In Chart

Results

Interaction with helmet donning

A A A A A B B B B B C C C C C F F F F F Average Average Average Average Average

• 1
• 0.5

0.5 1 Ease of Fitting Earplugs into the Ear Channels Earplugs Comfort without a Helmet Donned Ease of Donning Helmet with Earplugs Fitted Earplugs Comfort with a Helmet Donned Ease of Adjusting Earplugs with Helmet Donned

Results

In-flight Comfort

A A A A B B B B C C C C F F F F Average Average Average Average

• 1
• 0.5

0.5 1 Overall Comfort during Ascent Overall Comfort during Cruise Overall Comfort during Descent Ease of Ear Clearing during Flight

Results

A A A A A B B B B B C C C C C F F F F F Average Average Average Average Average

• 1
• 0.5

0.5 1 Clarity of Main Comms On- Ground Clarity of S/By Comms On- Ground Clarity of Main Comms In-Flight- Min Ambient Noise Clarity of Main Comms In-Flight- Max Ambient Noise Clarity of S/By Comms In-Flight- Max Ambient Noise

Comm Quality With Earplugs Working

Results

A A A A A B B B B B C C C C C Average Average Average Average Average

• 1
• 0.5

0.5 1 Clarity of Main Comms On- Ground Clarity of S/By Comms On- Ground Clarity of Main Comms In-Flight- Min Ambient Noise Clarity of Main Comms In-Flight- Max Ambient Noise Clarity of S/By Comms In-Flight- Max Ambient Noise

Comm Quality With Ear Plug Not Working

RAF Centre of Aviation Medicine

Discussion

• Custom Moulded Again More Comfortable
• IECD “A” And “B” Rated Higher On Comm

Quality When Working

– Followed By “C” Then “F”

• IECD “A” Outperformed Custom Moulded In

Comm Quality When IECD Not Working

– Followed By “C” Then “B”

RAF Centre of Aviation Medicine

Comments

• Too Much Noise Protection With Custom

Moulded

• Volume Set To Min When IECD Working
• Volume Set To Max When Not Working
• Audio Alarm Too Loud

RAF Centre of Aviation Medicine

Conclusions

• Custom Moulded More Comfortable Than

IECD “A”

– Trial Not Long Enough For Acclimation To IECD “A”

• IECD “A” Rated Better In Flight Performance
• Unable To Say One Is Better Than Other

RAF Centre of Aviation Medicine

Conclusions

• IECD “A” Is Flight Ready
• Work Is Needed On Custom Moulded

Systems Trialled To Make Flight Ready

• Work Is Needed On All IECD To Integrate To

– Helmet – Aircraft