insertion lossinsertion phaseinsertion voltage gaininsideinside diameterinside spiderinside surfaceinspectinspectioninstabilityinstability regioninstableinstallinstallationinstantinstant on switchinstantaneons valueinstantaneousinstantaneous accelerationinstantaneous automatic gain controlinstantaneous compandinginstantaneous currentinstantaneous frequencyinstantaneous particle velocityinstantaneous peak powerinstantaneous powerinstantaneous power outputinstantaneous readinginstantaneous recordinginstantaneous relayinstantaneous samplinginstantaneous sound pressureinstantaneous speech powerinstantaneous valueinstantaneous velocityinstantaneous voltageinstantaneous volume velocityinstitute of electrical and electronics engineersinstitute of high fidelityinstructioninstruction codeinstruction counterinstruction registerinstruction timeinstrumentinstrument approachinstrument approach systeminstrument flight rulesinstrument landinginstrument landing approach