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Sqn Ldr Parul Goel

I have no financial relationships to disclose

I will not discuss off-label use and/or investigational use in my presentation

Conventional aircraft +Gz acceleration

Gy accelerations rare

Studies 1960’s*

*Hershgold E. Roentgenographic study of humans during transverse acceleration. Aerospace Med. 1960;31:213-9

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Gy frequent

During “point”, “shoot” and “scoot” maneuvers (Super-agile aircraft)

Physiological response altered with Gy

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Effect of concurrent +Gy acceleration on +Gz tolerance

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Albery studied ±1/2Gy concurrent with +Gz *

↑in +Gz tolerance with concurrent Gy

*Albery WB. Acceleration in other axes affects +Gz tolerance: Dynamic centrifuge simulation of agile flight. Aviat. Space Environ. Med.

2004 Jan; 75(1): 1-6

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Popplow et al*

↓in arterial oxygen saturation ±1.5/2/2.5Gy & ±1/2Gz for 30s

Decreased arterial oxygen saturations

*Popplow JR, Veghte JH, Hudson KE. Cardiopulmonary responses to combined lateral and vertical acceleration. Aviat. Space

Environ. Med. 1983 Jul; 54(7): 632-6

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Scant literature

Contradictory findings

Necessity for further study

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High Performance Human Centrifuge (HPHC)

30 male

18-37 y

Institute Ethics Committee

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High Performance Human Centrifuge

High Performance Human Centrifuge

Control and Monitoring Station

Ejection Seat Mock Up with Five Point Harness System

Based on subjects’ experience:

Experienced [“E”]

Inexperienced [“IE”]

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Two centrifuge runs Run 1: pure +Gz run (0.1Gz/s) Run 2: combined acceleration run (+Gz/+2Gy)

+Gy *Baseline +1.4GzEnd point - +9Gz/Peripheral Light Loss

*Gell CF. Table of equivalents for acceleration terminology. Aerospace Medicine. 1961 Dec: 1109-11

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Baseline +1.4Gz

Profile 1 starts

+0.1Gz/sec

PLL/+9Gz

+Gz

Time

PURE +Gz Run

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Baseline +1.4Gz

0 Gy

Profile 2 begins

1Gy/sec

2 Gy

2Gy

+ 0.15Gz +0.1Gz/sec

PLL/+9Gz

+Gz/+2Gy Run

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LIGHT BAR

Dead Man Switch (DMS)

Head back

Heart Rate (HR)

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Dead Man Switch

Ejection seat mock up

Harness

Additional restraints

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Paired-t test

ANOVA with a post hoc tukey

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30 subjects 25 (83%) completed the protocol23 readings for +Gz tolerances 22 readings HR data

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No correlation

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ANTHROPOMETRIC DATA AGE 25.83±5.46 y

HEIGHT 171.7±5.89 cm WEIGHT 70.98±9.67 kg

The relaxed +Gz tolerance

“Pure +Gz” 4.46±0.51 Gz (3.21-5.28 Gz)

“Combined 5.07±0.62 Gz (3.31-5.95Gz) acceleration”

Mean ↑ in tolerance 0.61 Gz

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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 230.00.51.01.5

2.02.53.0

3.54.04.5

5.05.56.0

Comparison of +Gz Tolerance among both profiles

Subjects

+G

z To

lera

nce

+Gz RUN

+Gz/+2Gy RUN

No significant difference“E” & “IE” group

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↑ in HR with ↑ in level of acceleration

Combined acceleration > pure +Gz

HR at PLL

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Comparison of the HR during Run 1 and 2

+1Gz

+1.4G

z

+1.4G

z

+2Gz

+3Gz PL

L

+1Gz

(Bac

k)

3 sec

(pos

t sto

p)

100

120

140

160

180+Gz+Gz/+2Gy

+Gz ACCELERATION

HEA

RT R

ATE

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 220

50

100

150

200

250

HR AT PLL

SUBJECTS

HE

AR

T R

ATE

HR at PLL (+Gz Run)HR at PLL(+Gz/+2Gy Run)

↑ In relaxed +Gz tolerance

Albery (↑ of 0.4Gz - +2Gy)

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21/23 subjects - ↑ tolerance

Straining

↑ Venous return & peripheral vasoconstriction - ↑ in head level BP – ↑ +Gz tolerance

Straining tolerance likely to be similar

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Two mutually perpendicular accelerations

Increased magnitude and different direction

The visceral organs & vessels

↓ in hydrostatic effects

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Sensation of tumbling & being thrown out of seat

Fear & apprehension during the run - sympathetic system stimulation -↑ tolerance

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Nausea

Motion sick - ↑secretion of stress hormones

Albery - vestibular system

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Concurrent +2Gy contributed to a higher rise in HR

Better cardiovascular response

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A significant increase in +Gz tolerance (0.61Gz)

Better HR response

Straining by subjects & vestibular overstimulation

Contribute positively to the benefits of supermaneuverability

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Pure +Gz run

Combined acceleration run ‘Baseline’ of +1.4 Gz to +2Gy (+1Gy/s)Gz component steadily decreased to ~0Gz (+0.15 Gz)‘Pure Gy’ maintained for 1 sGz was gradually added at the

rate of 0.1 G/s

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Transient relative negative G

There was no significant difference in the HR at +1Gz and at +1Gz/+2Gy

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Effect of Concurrent +Gy Acceleration on +Gz ToleranceDisclosure Information 84th Annual AsMA Scientific Meeting Sqn Ldr Parul GoelSlide 3INTRODUCTIONSlide 5AIMPAST STUDIESSlide 8NEED FOR STUDYMATERIAL & METHODSSlide 11Slide 12Slide 13Slide 14Slide 15PROTOCOLSlide 17Slide 18Slide 19Slide 20Slide 21SEAT & HARNESSSTATISTICAL ANALYSISRESULTSRESULTS (CONTD.)Slide 26Slide 27Slide 28Slide 29Slide 30Slide 31DISCUSSIONDISCUSSIONSlide 34Slide 35Slide 36Slide 37CONCLUSIONSlide 39Slide 40Slide 41