# What would a plummeting plane sound like to a passenger? **URL:** \ **Category:** Factual Questions\ **Created:** [December 20, 2005, 12:10pm UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442 "2005-12-20T12:10:29Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![mittu](https://avatars.discourse-cdn.com/v4/letter/m/ecd19e/32.png) [@mittu](https://boards.straightdope.com/u/mittu)\ **Post date:** [December 20, 2005, 12:10pm UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/1 "2005-12-20T12:10:29Z")
I was watching a movie a few days ago that featured a large passenger plane playing an unsuccessful game of chicken with the Earth. In the scenes showing the passengers in the plane you could hear the plane’s engines becoming increasingly high pitched as it squealed towards the ground. I have never thought about it before but it occured to me that this probably shouldn’t happen. Wouldn’t the familiar high-pitched tone of the plane’s engines only be apparent to an observer on the ground as a result of the doppler effect? In my mind the engines would sound normal to passengers onboard the plane. Am I right or has Hollywood got it right this time? ---
**Author:** ![Richard\_Pearse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/richard_pearse/32/13144_2.png) [@Richard\_Pearse](https://boards.straightdope.com/u/Richard_Pearse)\ **Post date:** [December 20, 2005, 12:47pm UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/2 "2005-12-20T12:47:56Z")
You are right. An aeroplane diving towards the ground might have more airflow noise than usual, but the engine sounds will be dictated by the power setting. If the pilots haven’t changed the power setting then the engine note will be the same in the dive as in the cruise. ---
**Author:** ![Richard\_Pearse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/richard_pearse/32/13144_2.png) [@Richard\_Pearse](https://boards.straightdope.com/u/Richard_Pearse)\ **Post date:** [December 20, 2005, 12:50pm UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/3 "2005-12-20T12:50:17Z")
Some film makers will make the error even worse by using a screaming prop noise on a crashing jet. I can’t think of any examples asside from the parody in Airplane. ---
**Author:** ![An\_Arky](https://avatars.discourse-cdn.com/v4/letter/a/87869e/32.png) [@An\_Arky](https://boards.straightdope.com/u/An_Arky)\ **Post date:** [December 20, 2005, 1:00pm UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/4 "2005-12-20T13:00:48Z")
I’ll bet it gets drowned out by all those people people screaming ---
**Author:** ![pilot141](https://avatars.discourse-cdn.com/v4/letter/p/e0b2c6/32.png) [@pilot141](https://boards.straightdope.com/u/pilot141)\ **Post date:** [December 20, 2005, 2:56pm UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/5 "2005-12-20T14:56:01Z")
The increase in airflow noise would be almost imperceptible in the passenger cabin. It would be more noticeable up front, but how noticeable depends largely on the airplane. (The Boeing 727 is LOUD at max Mach; the McDonnell-Douglas MD-11 is very quiet at MMO). As **1920s Style “Death Ray”** pointed out the engine sounds would be dictated by the power setting. This is almost always depicted incorrectly in movies. When a jet descends the power is reduced; in fact we try to make descents at idle power (think of going down a big hill in a manual transmission car, but with no worries about the brakes - your engine is just along for the ride). Unfortunately in the movies when an airplane noses over it is almost always accompanied by an increase in engine noise/pitch. If you nosed over a passenger airliner and also increased the power you would quickly overspeed the airplane with possible disastrous results. Mach buffet, Mach tuck and many other control problems could mean an inability to recover from the dive and/or actual inflight separation of control surfaces. Regardless of what the pilots were doing you would hear almost nothing on the ground. The whole “speeding buzz” sound effect that Hollywood has associated with airplanes is (today) completely wrong. It worked in WWII when bombs had spinners on the nose to determine altitude and generated that characteristic “whine” but is useless in the jet age. Most jet engines produce most of their noise at the exhaust (back) end. Newer high-bypass fan engines surround that core exhaust with a huge fan bypass buffer, and as such are louder coming than going. But even so, the noise is a low growl, and not a high-pitched whine. Even if the pilots increased the power during a dive, a person on the ground would not hear anything until the jet impacted on top of them. The “high-pitched” effect is not due to Doppler shift, but due entirely to Hollywood’s disregard for the truth. ---
**Author:** ![matt](https://avatars.discourse-cdn.com/v4/letter/m/a6a055/32.png) [@matt](https://boards.straightdope.com/u/matt)\ **Post date:** [December 20, 2005, 3:20pm UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/6 "2005-12-20T15:20:25Z")
I’ve always thought this bit of cinematic licence comes from the “Stuka” dive bomber, which deliberately had sirens fitted to it to make it howl as it dived. The “diving aircraft” noise in movies may have developed from the portrayal of the Stuka in war films. [http://www.diggerhistory.info/pages-air-support/ww2-enemy/stuka.htm](http://www.diggerhistory.info/pages-air-support/ww2-enemy/stuka.htm) > [@pilot141](#): > > It worked in WWII when bombs had spinners on the nose to determine altitude and generated that characteristic “whine” but is useless in the jet age. I thought the spinners were an arming device! How do they determine altitude? Spin faster with greater air density? > [@pilot141](#): > > The “high-pitched” effect is not due to Doppler shift, but due entirely to Hollywood’s disregard for the truth. It’s never bothered me much, but it will now. The price of learning stuff, I guess! ---
**Author:** ![matt](https://avatars.discourse-cdn.com/v4/letter/m/a6a055/32.png) [@matt](https://boards.straightdope.com/u/matt)\ **Post date:** [December 20, 2005, 3:27pm UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/7 "2005-12-20T15:27:39Z")
Total hijack, but I had to share a tidbit of information from the end of my link given above: _“Only one Knights Cross to the Iron Cross with Oak Leaves, Swords and Diamonds was ever awarded. It went to Stuka pilot Hans-Ulrich Rudel, who flew 2,530 operational flights, and had over **500 Russian tanks and a Russian battleship to his credit** ”_ Colour me impressed! ---
**Author:** ![Xema](https://avatars.discourse-cdn.com/v4/letter/x/9de053/32.png) [@Xema](https://boards.straightdope.com/u/Xema)\ **Post date:** [December 20, 2005, 4:09pm UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/8 "2005-12-20T16:09:15Z")
> [@mittu](#): > > What would a plummeting plane sound like to a passenger? This would to some extent depend on the definition of “plummet.” There’s no inherent reason why a descent need be at a high speed. If the plane had suffered depressurization, the pilots would certainly be trying to get down to a “breathable” altitude quickly, but unless there’s also been a loss of flight control (unlikely due to backup systems) they’d be able to select the speed and rate of descent from a wide range of safe options. One of the common misconceptions is that when an airliner loses power, it “plummets.” In fact, it typically does a near-normal descent (perhaps at a somewhat lower-than-normal airspeed) and the only sensations would be less noise (due to engines not running and lower airspeed) and the ground getting slowly closer. ---
**Author:** ![lalaith](https://avatars.discourse-cdn.com/v4/letter/l/96bed5/32.png) [@lalaith](https://boards.straightdope.com/u/lalaith)\ **Post date:** [December 20, 2005, 4:50pm UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/9 "2005-12-20T16:50:16Z")
> [@pilot141](#): > > Even if the pilots increased the power during a dive, a person on the ground would not hear anything until the jet impacted on top of them. Got to dispute this one. Not that I know much about planes. I do, however, live below the landing path of an airport. So I know a hell of a lot about what prop planes and jets sound like from the ground when they are descending. Bloody noisy! Have to turn the tv up when some of those planes go over. All outside conversation either stops or has to be shouted. ---
**Author:** ![AzureM](https://avatars.discourse-cdn.com/v4/letter/a/ac91a4/32.png) [@AzureM](https://boards.straightdope.com/u/AzureM)\ **Post date:** [December 20, 2005, 5:05pm UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/10 "2005-12-20T17:05:55Z")
The only thing I have to add is a little personal experience. The occupant of a propeller-driven airplane in a dive does hear an increase in engine noise regardless of power setting. I was flying a Decathalon just the other day, and when I was pointed at the ground and my airspeed was increasing, the engine made more and more noise as the prop windmilled faster and faster. However, it was nothing like the whine that you hear in the movies. Just a sort of low pitched sound, kind of like if one were to blow on a desk fan. Keep in mind this is for piston airplanes. I don’t know about turboprops; I have never had the opportunity to fly one. Also, the little propellers on the front of bombs are called arming vanes. > [@](#): > > The M904 fuze arms and functions by the rotation of the arming vane and alignment of its internal components. When the fuze is released from the aircraft, the fuze arming wire is withdrawn from the fuze arming vane, and the arming vane is rotated by the airstream. Arming vane rotation is controlled by the constant arming action of the governor in the fuze. The arming vane continues to rotate until the preselected arming delay period (2 to 18 seconds) elapses (ends). Once the arming delay period elapses, the firing train is in full alignment and ready to function. [A]t impact, the forward part of the fuze body drives the striker body and firing pin down into the M9 delay element. After the proper delay, the M9 delay ignites the relay, detonator, lead, and booster,which sets off the main charge. [http://www.ordnance.org/fuzes.htm](http://www.ordnance.org/fuzes.htm) ---
**Author:** ![pilot141](https://avatars.discourse-cdn.com/v4/letter/p/e0b2c6/32.png) [@pilot141](https://boards.straightdope.com/u/pilot141)\ **Post date:** [December 20, 2005, 5:27pm UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/11 "2005-12-20T17:27:19Z")
> [@lalaith](#): > > Got to dispute this one. Not that I know much about planes. > > I do, however, live below the landing path of an airport. So I know a hell of a lot about what prop planes and jets sound like from the ground when they are descending. > > Bloody noisy! Have to turn the tv up when some of those planes go over. All outside conversation either stops or has to be shouted. I’m not saying that jets are quiet - I’m just saying that a jet diving at the ground will have a noise footprint no larger than a normal jet on approach. And for the people on board, things will sound normal. Again, most of the noise generated by jet engines is from the exhaust (the back). If a modern jet (lets say a 777) flew directly at you while you stood on a 200’ volcanic rock in the middle of the ocean…you would get hit by the airplane less than one second after you heard it approaching. Those engines are amazingly powerful and QUIET. Again…prop planes are different than jets. (And thanks to **AzureM** for digging up a link to the arming vanes on bombs! Enjoy your flying out there! ---
**Author:** ![Raguleader](https://avatars.discourse-cdn.com/v4/letter/r/258eb7/32.png) [@Raguleader](https://boards.straightdope.com/u/Raguleader)\ **Post date:** [December 20, 2005, 6:52pm UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/12 "2005-12-20T18:52:15Z")
> [@matt](#): > > I’ve always thought this bit of cinematic licence comes from the “Stuka” dive bomber, which deliberately had sirens fitted to it to make it howl as it dived. The “diving aircraft” noise in movies may have developed from the portrayal of the Stuka in war films. I’ve heard that the dive flaps on the SBD Dauntless dive bomber used by the US Navy in WWII also had the effect of making a banshee-like wail. Read a book about the Battle of Midway where Japanese sailors on one of the carriers reported the sound of four dive bomber squadrons coming down on top of them as a particularly unpleasant sound. ---
**Author:** ![Richard\_Pearse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/richard_pearse/32/13144_2.png) [@Richard\_Pearse](https://boards.straightdope.com/u/Richard_Pearse)\ **Post date:** [December 21, 2005, 2:47am UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/13 "2005-12-21T02:47:51Z")
> [@AzureM](#): > > The only thing I have to add is a little personal experience. The occupant of a propeller-driven airplane in a dive does hear an increase in engine noise regardless of power setting. I was flying a Decathalon just the other day, and when I was pointed at the ground and my airspeed was increasing, the engine made more and more noise as the prop windmilled faster and faster. You’ll find that the prop, if it’s _constant speed_, will only turn faster in a dive if it has reached its pitch limits. This would happen with a low power setting, the prop reaches its fine pitch limit and then acts like a fixed pitch prop. Normally though, a constant speed prop will maintain a constant rpm and there will be no increase in engine note. An aircraft with a fixed pitch prop such as a C152, C172, or Piper Cherokee, will increase its engine rpm in a dive and will sound different to anyone inside. ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [December 21, 2005, 3:43am UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/14 "2005-12-21T03:43:02Z")
When I was in a plane crash decades ago, all I heard was the roar of the engine, as we tried to regain airspeed. We were picking up nearly sufficient speed, but sadly ran out of altitude. ---
**Author:** ![Xema](https://avatars.discourse-cdn.com/v4/letter/x/9de053/32.png) [@Xema](https://boards.straightdope.com/u/Xema)\ **Post date:** [December 21, 2005, 3:50am UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/15 "2005-12-21T03:50:36Z")
> [@Qadgop the Mercotan](#): > > When I was in a plane crash decades ago… A single-engine plane, we infer. Can you tell us more? ---
**Author:** ![Richard\_Pearse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/richard_pearse/32/13144_2.png) [@Richard\_Pearse](https://boards.straightdope.com/u/Richard_Pearse)\ **Post date:** [December 21, 2005, 4:00am UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/16 "2005-12-21T04:00:11Z")
[**QTM** ’s plane crash.](http://boards.straightdope.com/sdmb/showpost.php?p=4742207&postcount=5) ---
**Author:** ![Xema](https://avatars.discourse-cdn.com/v4/letter/x/9de053/32.png) [@Xema](https://boards.straightdope.com/u/Xema)\ **Post date:** [December 21, 2005, 4:20am UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/17 "2005-12-21T04:20:49Z")
That’s quite a story. Glad QtM survived to enliven SDMB. ---
**Author:** ![Kevbo](https://avatars.discourse-cdn.com/v4/letter/k/e47774/32.png) [@Kevbo](https://boards.straightdope.com/u/Kevbo)\ **Post date:** [December 21, 2005, 6:39pm UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/18 "2005-12-21T18:39:57Z")
Lots of things on aircraft can whistle at high airspeed. I’m pretty sure the aformentiond Stuka did not have sirens fitted, but just perforated panels for dive brakes, which whistled. I own a Grob Astir CS sailplane which has a socket in the tailboom for a ground handling wheel. When going over 100 kt. it whistles loudly to observers on the ground, but is not audiable to me over the noise of the canopy seals. Sirens to increase dive noise do exist. I know at least one airshow pilot who has one of these: [http://www.i4cproducts.com/air\_screamer.htm](http://www.i4cproducts.com/air_screamer.htm) Fitted to his [Biplane](http://www.silentwingsairshows.com/biplane.html). ---
**Author:** ![matt](https://avatars.discourse-cdn.com/v4/letter/m/a6a055/32.png) [@matt](https://boards.straightdope.com/u/matt)\ **Post date:** [December 21, 2005, 7:41pm UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/19 "2005-12-21T19:41:11Z")
> [@Kevbo](#): > > Lots of things on aircraft can whistle at high airspeed. I’m pretty sure the aformentiond Stuka did not have sirens fitted, but just perforated panels for dive brakes, which whistled. It seems to depend on the model: [http://www.geocities.com/CapeCanaveral/2072/stuka.html](http://www.geocities.com/CapeCanaveral/2072/stuka.html) “the Berta would generate an eerie whine as it dove at an angle approaching 90° onto its target as the wind whistled through the extended airbrakes. This was distinctly unnerving for troops unaccustomed to it. Later an actual siren was developed to exploit the effect, which wreaked havoc when the Germans invaded the West in May 1940, and provided people with the most indelible impression of the Stuka.” And you just can’t find them anymore… [http://gf24.de/biplane/msg00758.html](http://gf24.de/biplane/msg00758.html) “There’s only a couple of Stuka dive bombers around. After the war, I read, we hired the Germans to dismantle their war machine (it also said this plane was slow and an easy target). One is in Chicago but doesn’t have the siren. It was rebuilt by the EAA and is on loan. There is another in England but it is a model JU87-G. As far as I can tell, only the early model B’s had a siren. I then found a national museum in Germany, but they only have a text description and some simple 3-d drawings, no manufacturing drawings” Sorry I couldnt find an authoritative cite, but if it’s a legend it’s a really well established legend! ---
**Author:** ![Spectre\_of\_Pithecanthropus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/spectre_of_pithecanthropus/32/12343_2.png) [@Spectre\_of\_Pithecanthropus](https://boards.straightdope.com/u/Spectre_of_Pithecanthropus)\ **Post date:** [December 21, 2005, 11:46pm UTC](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442/20 "2005-12-21T23:46:52Z")
I’m confused. There’s the typical Hollywood movie sound of an airplane out of fuel, making a controlled but steep descent, and accompanied by a sort of long drawn out howl that sounds a little like the sound of a car horn in a tunnel. Is this the sound everyone’s talking about? [Next page](https://boards.straightdope.com/t/what-would-a-plummeting-plane-sound-like-to-a-passenger/336442.md?page=2)