Why are there speed limits?

Speed limits are like having laws in them sky. They are entirely essential so to get rid of them on IF is just stupid.


Aircraft do not break those speed limits, KIAS and kts ground speed are two completely different things.

Grammarly is freaking out at me, so I took the liberty of proofreading the quote.

If you’re having issues with controlling the aircraft, learn how to fly the thing and make good use of the calibration and autospeed tools.


Yeah I sort of understand where you’re coming from with this and I’m not having a go at you but if you listen to some real world ATC they do give instructions to pilots like “there are no current speed restrictions” or “speed at your discretion” generally only if it’s not a busy airspace and I’ve noticed it’s usually given once cleared for takeoff or transitioning. In saying that though the pilots at the end of the day are responsible for flying the aircraft within its limitations and in a safe and controlled manner. I know it’s sometimes difficult when taking off and climbing out to FL100 to stay under IAS 250knts but as stated above in real life ATC do allow pilots to exceed this restriction eg. when taking off and if the airspace permits it. I hope this helps.

Most planes climb out at 200KIAS due to ClassB-D airspace speed restrictions. Once they are above 4000+ the can accelerate to 250KIAS. All these rules are rules ever pilot must follow in real life regardless of continent.


In real life, it has to do with sound. Jets are really loud and the faster they go, the louder they get. They set the speed limit under 10,000 feet so that people on the ground won’t have to listen to screaming jets all the time.

@Tecnam2TA incorrect. Noise abatement procedures and certain takeoff procedures are used to avoid noise over highly populated areas. The 250 knot IAS has nothing to do with it.

‘Speed’ doesn’t cause sound. Engine thrust and drag causes sound, and couple it with the proximity to the ground.


I thought I remembered reading that somewhere. My mistake.

Exactly. You increase throttle to gain speed. In return the engines produce more sound. The speed itself doesn’t cause an increase in sound.

What you are failing to realize, is that the speed you see on the flight tracking apps or sites, is given in GROUND speed and not INDICATED air speed. They are two different speeds. The speed limits that we have implemented into the sim are very realistic as they are based on KIAS (knots indicated air speed). The ones you see flying 620 again are in ground speed as well as have a very strong tail wind. The 250 KIAS below 10,000 feet is as realistic as it gets. The 350 KIAS limitation is more than fast enough within the limited space of the regions, however it is VERY realistic as well. If you want to fly faster, then fly on the Casualserver.



im not debating those points, and the point you made about clowns flying around at mach speed are true enough, i see them everyday. im not talking about flying with the burners on all the time either, im kina like you, i think flying with finesse and deliberation are more important than just getting from a to b, n the shortest amount of time.
what im saying is, what ive learned from ‘planes live’ is that, IF doesnt really reflect real world aviation, as far as speed is concerned. those images i posted r the rule and not exceptions, id say since ive had ‘planes live’ 90% of the time, anything from 737s on up to a380-8s are climbing out of 2 to 3k ft at 250kts or above. most of those same planes by the time theyve reached 10k ft, r usually over 350kts, or about to punch through it.
i just want parity, if IF is suppose to reflect real world aviation i think they might need to revisit speed limits. im not against them…at all. like i said, if IF keeps the limits at what they r, im gonna abide by them, unless i unintentionally go over them. which im sure everyone does from time to time.

i believe 1 knot is appox 1.71 mph. if im not mistaken, i know theres not a significant diff. i mean at higher speeds it becomes significant to a degree…but its apples and oranges. i know this, at 10kft, most planes are well over 350 kts. at 30k ft or above 350 kts is just contrary to the design of the plane. the only exception i could see for being at 350kts at cruising alt is weather, thats why they have weather divert routes, i believe thats the correct term.


On the flight tracking apps it show you the Aircrafts GROUNDSPEED.
AIRSPEED and GROUNDSPEED are NOT the same thing.

It is a REAL limit in the real world.

But if for some reason you don’t believe us we then here is a post made by Tyler in a different thread.


Oh, my god.

It was at this point that he realised he was about to lose it.

As Mark explained, the speed limits ARE already realistic, it’s just that YOU can’t seem to be able to understand properly the difference between Ground Speed, KIAS etc.


@Brit1 I’ll make it as simple as I can.

ALL apps such as ‘planes live’ and ‘flight radar’ etc, ONLY display the aircrafts groundspeed. They do not have the capability to display the indicated airspeed f each aircraft, as they are not directly hooked up to the pitot tubes and the flight deck of an aircraft. It’s using radar based data to calculate ground speeds to display to you on your ‘planes live’ app.

Please do some research on ground speed and indicated airspeed.

The limit in IF, and the regulations under the FAA FAR, relate to maintaining 250 knots indicated airspeed and under (unless exceptions are made), the exceptions which, as we keep stating, are not the norm for every single flight. They are an exception to the rule.

Due to the constantly lowering air density as your altitude increases, the speed you travel over the ground grows incredibility versus your indicated airspeed, which actually reduces (if you were to maintain the exact ground speed). Therefore, read this carefully, at 10,000feet, if you are flying at an indicated airspeed of 250 knots, your ground speed (as shown on your ‘planes live’ app, to be clear here) would most likely read something like 320knots, and something like 350 mph (depending on which unit of measure the app is using). This is WHY YOU ARE SEEING SPEEDS of about 320 knots to 350 knots. The IF restrictions relate only to the indicated airspeed under 10,000feet.

Please, give it a rest, this is just getting frustrating



1kt = 1.15mph

IAS is different than ground speed.


I love how this guy has come up with his own theory about the two speeds being the same, regardless that everyone keeps on telling him that groundspeed is different from KIAS. Keep on fighting a losing battle instead of looking it up on the internet xD


He did this on another topic…

Why hasn’t this thread been closed yet?? I don’t think anyone can explain it any better than we already have to him…


that’s what i was about to say. this thread should have closed quite some posts back.


I believe that you are mistaken and that after every…single…explanation by everyone on this thread telling you that it has NOTHING to do with MPH! 🙄
We have more than explained the difference to you, but I believe that you refuse to accept any of the above responses. You simply refuse to understand what we have explained. Do some research and self study on this since our CORRECT responses are not sufficient enough for you.