Reduced Vertical Seperation Minimums (RVSM)

FrankieFlyCRQ

Well-Known Member
Just wanted to clarify somthing about RVSM..

Ok soo according to the Instrument Jepp book, the definition of RVSM is any airspace between FL290 - FL410, where airplanes are seperated by 1,000 feet vertically.

My question is what is the vertical seperation minimums between FL180 - FL290, or even victor airways 1,200 - FL180 or is there any at all below FL290 and if so how does ATC determine the seperation altitude between odd and even headings? I cannot find the answer anywhere.

This is all I found in the AIM which doesnt really answer my question unless I overlooked it :
4-4-11. IFR Separation Standards
a. ATC effects separation of aircraft vertically by assigning different altitudes; longitudinally by providing an interval expressed in time or distance between aircraft on the same, converging, or crossing courses, and laterally by assigning different flight paths.
b. Separation will be provided between all aircraft operating on IFR flight plans except during that part of the flight (outside Class B airspace or a TRSA) being conducted on a VFR-on-top/VFR conditions clearance. Under these conditions, ATC may issue traffic advisories, but it is the sole responsibility of the pilot to be vigilant so as to see and avoid other aircraft.
c. When radar is employed in the separation of aircraft at the same altitude, a minimum of 3 miles separation is provided between aircraft operating within 40 miles of the radar antenna site, and 5 miles between aircraft operating beyond 40 miles from the antenna site. These minima may be increased or decreased in certain specific situations.
NOTE-
Certain separation standards are increased in the terminal environment when CENRAP is being utilized.

Anyone know what the seperation is if any:confused:
 
My question is what is the vertical seperation minimums between FL180 - FL290, or even victor airways 1,200 - FL180 or is there any at all below FL290 and if so how does ATC determine the seperation altitude between odd and even headings? I cannot find the answer anywhere.

The vertical separation minima between IFR aircraft below FL410 is 1000', unless visual separation is applied (up to the 2 pilots in that case). The reason the airspace between FL290 and FL410 is called REDUCED VSM is that it USED to be 2000' separation. To facilitate the increase in air traffic over the past 10 years, the FAA finally implemented the 1000' standard.

http://www.faa.gov/airports_airtraf...tions/ATPubs/ATC/Chp4/atc0405.html#qGM230JACK
 
Ok so this makes better sense, everything under FL410 is 2,000 feet seperation but between FL290 - FL410 RVSM applies for aircraft except for non-RVSM aircraft which is still 2,000 right??


b. Apply 2,000 feet at or above FL 290 between non-RVSM aircraft and all other aircraft at or abovFL 290.

So what determines a non-RVSM aircraft?

Everything else I understand. Thanks for the clarification.

 
In order for aircraft to fly in RVSM airspace, aircraft need:
[FONT=Verdana, Arial, Helvetica, sans-serif]• Two independent altitude measurement systems meeting the system error requirements.[/FONT]

[FONT=Verdana, Arial, Helvetica, sans-serif]• One autopilot system capable of keeping the aircraft altitude within ±20 m (±65 ft).[/FONT]

[FONT=Verdana, Arial, Helvetica, sans-serif]• One altitude alert system with limits ±90 m (±300 ft).[/FONT]

[FONT=Verdana, Arial, Helvetica, sans-serif]• One secondary surveillance radar (SSR) altitude reporting transponder.[/FONT]

[FONT=Verdana, Arial, Helvetica, sans-serif]• RVSM compliant avionics configuration.[/FONT]

There are lots of non-RVSM compliant aircraft out there -- US military fighters being one of them! Keeping all fighters and trainers below FL280 has really cut the cross-country legs short!
 
Gotcha! Interesting stuff thanks.
If you like we can also discuss the differences between RVSM and MNPS separation/alititudes and airspace, and aircraft requirements?

IE an aircraft being legal in RVSM but not in MNPS airspace.

Also in Canada anyway there are only a few aircraft allowed in RVSM airspace when not certified RVSM... these are the three main ones, I think theres some allowance for photo surveys and such, but I've never seen anything like that.

1.)State Aircraft (Government)
2.)Delivery flight
3.)Aircraft non-rvsm certified, climbing above or descending below RVSM airspace (IE a biz jet climbing to FL430 or above)
 
Don't forget about RNP10/4

Oceanic went to RVSM back in 2000/01 (I forget exactly) and we went to DRVSM a few years ago... I want to say 04 maybe ?
 
Don't forget about RNP10/4

Oceanic went to RVSM back in 2000/01 (I forget exactly) and we went to DRVSM a few years ago... I want to say 04 maybe ?

You wouldn't happen to know what kind of increased workload/hassle it is for Oceanic to handle a non-RNP10 aircraft on the WATRS Plus route structure, would you? Reason I ask is that we recently flew down to the Dominican Republic and, in compliance with the NOTAMs, informed ARINC that we were non-RNP10 upon checking in. No further comment was made on their behalf, and we weren't deviated from our flightplanned route. In a push to get the company I fly for to dump some money into more advanced avionics (RNP compliant), we made the comment to them that at any time, they could have denied us access to the airspace and caused us to divert for fuel as our flightplan called for a max endurance run even if we were cleared as filed. I know thats not fully the truth, but I am curious as to how often they deviate or deny non-RNP10 aircraft.
 
With the latest airspace restructuring within WATRS airspace, the new airways have gone from 60NM lateral to 50NM lateral separation, and now allows more traffic within the airspace as a whole. In order to utilize these routes aircraft must be RNP 10 compliant, if they are anything other then they still need to apply 60NM lateral, or of course the obvious vertical.

Now all that being said, I work on a daily basis with NY Oceanic and we give/recieve flights to and from each other all the time, and I have not been told on our end, or by New York to differentiate separation based on different levels of RNP certification, that type of separation is New Yorks responsibility, but I've never had flights denied because of a lower level of RNP certification.

In fact we've just recently drastically reduced the required longitudinal separation (Time in minutes) for airplanes entering from NY's Airspace, now if I'm not mistaken the airspace which we control (some of which belongs to NY but we have radar so we control it) is actually NAT-A airspace not WATRS airspace (unless it changed in June), I'm not sure why most of NY Oceans airspace is WATRS except for a small portion, and I'm not sure the reasons that it differs and what rules if any change, although I'm of the belief the rules relating to RNP are the same considering the fact we get approval from NY and we have to issue a full route clearance to destination (including portions in WATRS) to every airplane leaving our RNPC airspace into non-radar..
 
You wouldn't happen to know what kind of increased workload/hassle it is for Oceanic to handle a non-RNP10 aircraft on the WATRS Plus route structure, would you? Reason I ask is that we recently flew down to the Dominican Republic and, in compliance with the NOTAMs, informed ARINC that we were non-RNP10 upon checking in. No further comment was made on their behalf, and we weren't deviated from our flightplanned route. In a push to get the company I fly for to dump some money into more advanced avionics (RNP compliant), we made the comment to them that at any time, they could have denied us access to the airspace and caused us to divert for fuel as our flightplan called for a max endurance run even if we were cleared as filed. I know thats not fully the truth, but I am curious as to how often they deviate or deny non-RNP10 aircraft.

WATRS+ airspace is not exclusionary like RVSM. You can fly in WATRS+ airspace and be non RNP10 (or 4). You may get a reroute due to not having the proper lateral seperation from certain airspace or may not get a good altitude due to not having sufficient seperation with aircraft on parallel routes. You can also get denied deviaitons, again due to not having sufficient lateral seperation.

These are all factors due to times of heavier volume.

You'll never get denied access... you just won't have the level of service that an RNP10/4 aircraft would have. Non RNP10/4 aircraft do not involve a increased workload/hassle on the controllers side.
 
With the latest airspace restructuring within WATRS airspace, the new airways have gone from 60NM lateral to 50NM lateral separation, and now allows more traffic within the airspace as a whole. In order to utilize these routes aircraft must be RNP 10 compliant, if they are anything other then they still need to apply 60NM lateral, or of course the obvious vertical.

Now all that being said, I work on a daily basis with NY Oceanic and we give/recieve flights to and from each other all the time, and I have not been told on our end, or by New York to differentiate separation based on different levels of RNP certification, that type of separation is New Yorks responsibility, but I've never had flights denied because of a lower level of RNP certification.

In fact we've just recently drastically reduced the required longitudinal separation (Time in minutes) for airplanes entering from NY's Airspace, now if I'm not mistaken the airspace which we control (some of which belongs to NY but we have radar so we control it) is actually NAT-A airspace not WATRS airspace (unless it changed in June), I'm not sure why most of NY Oceans airspace is WATRS except for a small portion, and I'm not sure the reasons that it differs and what rules if any change, although I'm of the belief the rules relating to RNP are the same considering the fact we get approval from NY and we have to issue a full route clearance to destination (including portions in WATRS) to every airplane leaving our RNPC airspace into non-radar..

WATRS airspace actually went from 90 miles down to 50. 60 miles could only be used for MNPS aircraft but the north / south flights are not MNPS equipped (most are not). Composite separation (75 miles) was used between MNPS and non MNPS equipped aircraft.

The MNPS requirement begins at 60W if memory serves...
 
everything under FL410 is 2,000 feet seperation but between FL290 - FL410 RVSM applies for aircraft except for non-RVSM aircraft which is still 2,000


That is not quite right.

Below FL290 separation is 1000 feet between ALL aircraft.
Between FL290-FL410 separation is 1000 feet between RVSM aircraft
Between FL290-FL410 separation is 2000 feet between Non-RVSM and other aircraft.
Between FL410-FL600 separation is 2000 feet between ALL aircraft
Above FL600 separation is 5000 feet (between U2, ER2, WB57, or whatever else makes it way up there)

As someone already stated, there are exceptions to who is allowed in RVSM airspace and NOT RVSM qualified:

  • DOD
  • Lifeguard
  • Manufacturer aircraft being flown for development/certification
  • Foreign State aircraft
 
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