Jet approach altitude profiles?


#1

I’m about to move into a home that is along one of the approach corridors for KRDU, about 4.5 miles from the end of the runway.

For my own edification, I’d like to know just how far up these planes will be as they pass overhead. Does anyone know of a resource that lists typical approach altitude profiles for common jets? I’m mostly interested in 737 (all variants except 200) and MD-80 carrier jets, and Canadair and Embraer regional jets (smaller air taxi variants).

Or is this something that is airport-specific and determined by the ATCs?

Thanks!

Hal


#2

Hal,

“Generally speaking”, all planes will follow a certain flight profile especially for instrument approaches so the height will be pretty consistent on the descent profile for all planes, whether it be a little guy like me or a jst jockey.

Not sure how familiar you are with reading instrument procedures, but they all can be located flightaware.com/resources/airport/KRDU.

A typical approach would look like flightaware.com/resources/airpor … OC+RWY+23L This approach is for runway 23 taking from the above resource page.

Hope this helps.

Allen


#3

I case you haven’t read the approach plates that Alan is pointing you to, they basically say that a plane is around 200’ above ground level (agl) about a half mile from the airport, 700’ at 2 miles and 1800’ at 6 miles, all on a straight path to the active runway (which runway that will be changes with the wind). However, you may be more concerned about departures where planes are near full power. Climb rates are highly variable depending on temperature, load and power, but one benchmark would be a jet climbing at 1500 feet per minute and an airspeed of 120 miles per hour would be climbing about 3000 feet per mile from the liftoff point. These are usually straight out for the initial climb and then a turn on course.


#4

Using the Runway 23L example above, it shows 1,800’ above sea level at 4.5 miles. Subtracting the elevation at the touchdown zone of 435’, that puts it at a little less than 1,400 feet above the ground at 4.5 miles.


#5

We’re in the corridor for 23R, so by what you say and flightaware.com/resources/airpor … WY+23R/pdf, it looks like at 4.5nm they should be around 2200’ above MSL, or just under 1800’ up. Is that correct?

How much noise should we expect from jets at that altitude? By luck of the draw, we’ve only ever been out at the property on 5L/5R days, and the departure paths aren’t anywhere near there.

Thanks for all your help!

Hal


#6

It appears that BODLY, the final approach fix, is 5.4 miles from the end of rwy 23R. All aircraft on the ILS approach will cross BODLY at 2200’ msl which would be approx 1700’/1800’ above ground. Your house is about a mile inside of the FAF, so figure 300’ or so lower, so about 1400’ agl over your house.


#7

More careful measurement on the map shows about 6.2NM (7.13 statute miles) between the end of the runway and the house. If I did the math right, then the altitude is just over 2300’ msl, or just under 1900’ agl.

It’s got my wife a bit freaked out, since we literally hadn’t seen a single plane in the 10-12 hours we spent on the property, on five different days, spread out over two months. But at 1900’, I feel a little more comfortable that we won’t be too disturbed by the traffic.

Hal


#8

Sound can do some strange things.

Landings probably won’t be your “noise problems”

As CAFlier mentions, takeoffs will be noisier even though they may be higher. Most planes do a significant amount of climbing over the airport environment to help reduce noise, but the noise from planes at full power will go a lot further then landing traffic which have engines running at reduced power.

You may want to gander at the “DP” (Departure) procedures on the resource page and you might be able to extrapolate that information for your needs. The “four digit numbers” along the lines (3000 would be 3000 feet) are altitudes the plane uses on standard departures.

Departure procedures are preferred methods, but not mandatory so the altitude and path could vary for a pilot that does not elect to use the DP.

Allen


#9

Just throw a fuss and get the airport closed.


#10

I’m actually not concerned about takeoffs. KRDU has a really handy interactive map that shows arrival and departure patterns for both directions (5/23), based on actual flight data for two different days. The house is in an little island that is totally free of departing flights, for about a half-mile in all directions. And that jibes with our experience on site, which was that we never noticed a single plane in many hours.

I’ll definitely check out the departure procedures.

The KRDU flight track map is at 198.85.228.132/rdu/viewer.htm, if you’re curious.

Thanks so much for all the information!

Hal


#11

Dude! You’re funny!!! :laughing:


#12

Or create a website showing how low the planes are flying, file complaints with every government agency and then complain that the pilots are purposely harrassing you!


#13

Niiiiiiiiiice!


#14

…and argue about how it should be closed for its inconvenience even though it was there FIRST. And make sure you get some money out of this. :smiley: :smiley:


#15

Be sure and sue your real estate agent for even showing you the property!


#16

When I worked on airspace design and noise abatement procedures the rule of thumb we used is that unless there were mitigating circumstances (read obstruction) ariivals decesnded at 300 feet per mile and departures climbed at 600 feet per mile.

This figure was an average that we could use when we put lines to a map.

When we went to the public during environmental impact meetings most of the complaints we received were from landowners living within 5-6 miles from the airport. The key word is airport. That includes departure and arrival/aproach routes.

We could only tell these people that within those 5 or 6 miles there will always be the potential for overflights simply because of the number of aircraft using the airport and ATCs need to safely space aircraft and the potential for visual approaches by all type aircraft from different directions.

Outside of that 5-6 mile area aircraft would normally be at or above the minimum radar vectoring altitude and ATC would have more discretion concerning overflights.

It was a fact of life and little could be done close in to the field. They didn’t like it but that was that.

I’ve lived near airports all my life and I was always required to sign a statement before I contracted for the purchase that I was aware that I was close to such and such airport and there would be aircraft noise.