How loud is the F-35?

Salute!

There are concerns here at Eglin about noise when the F-35 arrives.

Is the thing louder than a Viper in burner? Or an Eagle?

My thinking is the noise concern is due to the number of flights the F-35 will be making here, being the main training base and having more jets than the 33rd Wing.

So there must be a formula that the government uses, huh? Like number of operations, basic decibels, durations of the decibels, and the beat goes on.

Gums sends ...

From what I heard the F-22 is a lot less loud then a F-15 so a F-35 will probably be less loud then a F-16.

Kaasjager. wrote:from what i heard the F-22 is allot less loud then a F-15 so a F-35 will probably be less loud then a F-16.

Could it be that the F-22 and F-35 don't need to do afterburner takeoffs as often? Because I'm pretty sure an F119 is going to be louder than an F100 in full afterburner.

Gums wrote:Salute!

There are concerns here at Eglin about noise when the F-35 arrives.

Is the thing louder than a Viper in burner? Or an Eagle?

My thinking is the noise concern is due to the number of flights the F-35 will be making here, being the main training base and having more jets than the 33rd Wing.

So there must be a formula that the government uses, huh? Like number of operations, basic decibels, durations of the decibels, and the beat goes on.

Gums sends ...

Some figures on page 5 here:

http://www-nehc.med.navy.mil/downloads/ ... ection.ppt

Regards,
Bjørnar

energo wrote:

Gums wrote:Salute!

There are concerns here at Eglin about noise when the F-35 arrives.

Is the thing louder than a Viper in burner? Or an Eagle?

My thinking is the noise concern is due to the number of flights the F-35 will be making here, being the main training base and having more jets than the 33rd Wing.

So there must be a formula that the government uses, huh? Like number of operations, basic decibels, durations of the decibels, and the beat goes on.

Gums sends ...

Some figures on page 5 here:

http://www-nehc.med.navy.mil/downloads/ ... ection.ppt

Regards,
Bjørnar

Interesting that the F-35 is almost as loud as an F-14D in full afterbuner even though it only has ONE engine.

I agree the F-35\F135 will be louder than any of the aircraft it replaces.

Air Force officials have acknowledged that the F-35 will be substantially louder than the jets it replaces. But precise data has not been available because the engine was still under development until recently.

The statement of the F-22\F119 is correct in the respect that less MAX-AB take-offs makes the local area seem quieter. The Raptor can also climb out quicker, which will make the ground footprint of the noise seem smaller.

Seems being the key word, the F119 will make more noise than the F100 in most respects. It may not have the shrill whine of the compressor, but the low freq exhaust noise is higher.

Even going from a F100-PW-220 to the PW-229 will increase noise. With the added exhaust gas velocity it creates more "friction" or turbulence with the surrounding air. This is the bulk of the roar you hear.

Read here: http://cobweb.ecn.purdue.edu/~propulsi/ ... noise.html

Now at MIL power the F135 engine may be a little quieter than the F119, as the F135 has a higher bypass-ratio which should lower the overall exhaust velocity at MIL, (done to gain single engine efficiency) but at MAX-AB it should be louder due to the additional oxygen (and resulting fuel flow) available for combustion in the 'burner. More O2 + More JP8 + advance aerodynamic mixing and control technologies = 40K pounds of thrust = "The Sound of Freedom" over a very large area.

Keep 'em flyin' ...and wear that hearing protection!
TEG

Best guess, imo, F-35 could seem about 35%-40% relatively louder than F-16 depending on either mil power or AB.

The F-35 is definately louder than a F-16 or F-18. It probably isnt louder than a F-15, but I know when they tested the flightline runstations for F-35 ops, they brought in a F-15 to duplicate the noise levels. And its got the coolest howling noise when the pilot first goes to MIL power. Its sweet.

LMAggie wrote:The F-35 is definately louder than a F-16 or F-18. It probably isnt louder than a F-15, but I know when theyed tested the flightline runstations for F-35 ops, they brought in a F-15 to duplicate the noise levels. And its got the coolest howling noise when the pilot first goes to MIL power. Its sweet.

According to that Powerpoint presentation it's louder than the F-15. Didn't say if it was a -220 or -229 they were comparing it to though. Probably -220

sferrin wrote:

LMAggie wrote:The F-35 is definately louder than a F-16 or F-18. It probably isnt louder than a F-15, but I know when theyed tested the flightline runstations for F-35 ops, they brought in a F-15 to duplicate the noise levels. And its got the coolest howling noise when the pilot first goes to MIL power. Its sweet.

According to that Powerpoint presentation it's louder than the F-15. Didn't say if it was a -220 or -229 they were comparing it to though. Probably -220

It's a beast. I've stood in the runstation during one of BF-1's mil power engine runs. It was amazing. And apparently the afterburner runs charred the grass behind the thrust ramps. That doesnt happen with F-16's.

I'll log on long enough to put the F-22 sound issue to bed. The F-22 is much louder than the F-15.

Here is a link: http://www-nehc.med.navy.mil/downloa...Protection.ppt

Basically the F-35 is 3 dB louder than the F-15. Also a recent study done in Alaska, the F-22 noise levels matched those of the F/A-18.

Noise levels in dB also known as decibels. The more dB the louder.

EA-6 148 dB
F-14(full AB) 153 dB
F-16(full AB) 150 dB
F-18F(military power) 150 dB
F-15C(full AB) 149 dB
F-35 JSF(full AB) 152 dB

Here is a draft environmental study for F-35 bed down at Nellis within Clark County.

Noise charts on page 117 for various engines from idle to mil. F-35 is louder than the rest and the 3db increase is used in all studies.

Funny thing is afterburner (use search function) is only mentioned twice in this whole report.

Isn’t that when the engine is the loudest? Nevertheless, the louder the
better.

http://budget.state.nv.us/clearinghouse ... 08-419.pdf

VarkVet wrote:Here is a draft environmental study for F-35 bed down at Nellis within Clark County.

Noise charts on page 117 for various engines from idle to mil. F-35 is louder than the rest and the 3db increase is used in all studies.

Funny thing is afterburner (use search function) is only mentioned twice in this whole report.

Isn’t that when the engine is the loudest? Nevertheless, the louder the
better.

http://budget.state.nv.us/clearinghouse ... 08-419.pdf

The F-35 is going to be loud, the 3dB difference in noise levels is equal to a doubling of the noise level. Remember the decibel scale is logarithmic so a doubling of the intensity a sound or noise always causes an increase of approximately 3 dB.

asiatrails wrote:
The F-35 is going to be loud, the 3dB difference in noise levels is equal to a doubling of the noise level. Remember the decibel scale is logarithmic so a doubling of the intensity a sound or noise always causes an increase of approximately 3 dB.

Well, thats hardly surprising. Noise is largely a factor of the amount of thrust being made and the nozzle area that thrust is exiting from. The F-35 has probably one of the highest if not the highest thrust to nozzle area ratios.

Basically, it comes down to thrust being made by pressure and volume of exhaust products. Nozzle area determines the velocity of the jet plume and mixing front between atmospheric pressure air and the pressurized discharge. 43,000 lbs is a lot of thrust -- it is roughly what propels an Airbus A320 or a newer Boeing 737 at take off from those two CFM56 engines. The exhaust area on the F135 engine is a heck of a lot smaller than that of those two high bypass turbofans combined probably something on the order of 1/5~1/6th the size.