If on an IFR flight plan, are you saying that we need to VFR charts to know what the MSA is, and have them readily available during IFR conditions? I thought ATC used Minimum Vectoring Altitudes for the area we fly, and I’ve never seen a MVA chart for sale at my local FBO, what gives?
Jim,
You are always responsible for your minimum altitudes per FAR 91.177 (see below). The MVA (or MIA) typically gives you the proper separation from obstructions. That’s when you are on a vector. Now, if ATC says, “clear direct xyz VOR” then you are no longer being vectored and need to figure out what the minimum off route altitude needs to be per FAR 91.177. The VFR sectional chart provides such information fairly accurately. Or you can use the OROCA on the IFR en route charts.
In reality, ATC won’t let you fly at an altitude (even when cleared direct) that is below their MVA (or MIA). But, they are never “responsible” for your terrain separation. That’s your problem.
It has been found that some MVAs are not in compliance with FAR 91.177. You can gain access to the MVAs through the Freedom of Information Act. You won’t get them at your FBO.
91.177 Minimum altitudes for IFR operations.
(a) Operation of aircraft at minimum altitudes. Except when necessary for takeoff or landing, no person may operate an aircraft under IFR below -
(1) The applicable minimum altitudes prescribed in Parts 95 and 97 of this chapter; or
(2) If no applicable minimum altitude is prescribed in those parts -
(i) In the case of operations over an area designated as a mountainous area in part 95, an altitude of 2,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown; or
(ii) In any other case, an altitude of 1,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown.
However, if both a MEA and a MOCA are prescribed for a particular route or route segment, a person may operate an aircraft below the MEA down to, but not below, the MOCA, when within 22 nautical miles of the VOR concerned (based on the pilot's reasonable estimate of that distance).
The method you describe is a great technique for those times you have already programmed the route in the Garmin. In this case it would have worked perfectly. Flying the SBA Lima 3 TEC to Santa Ana I use this every time.
There is also another technique that works well when you get a vector to a new airway you were not expected, and thus is NOT in the Garmin flight plan yet. Here is how it works:
Assume ATC says “fly heading 280 and join Victor 8 to Seal Beach”. You would then twist HDG 280 and let the AP fly. Then press Direct on the Garmin, put SLI in as the way point, cursor down to the CRS (course) field and enter the TO radial for that airway (238 in this example) and then activate. Your active leg will now be V8 to SLI. Press HDG-NAV and off you go. Make sure you enter the TO radial and not the FROM.
Rich,
I got caught in a similar SNA Anaheim 3 departure SNAFU about a year ago. The rapid fire reroutes with “embedded” frequency changes caused me to fall behind the aircraft. It was a very very bad feeling.
Things I learned:
Have the VORs set up for the departure and use them. ATC is thinking VOR fixes and connecting airways. GNS 430 buttonology takes too long to manage in this environment, esp. if the wx is IMC.
Study the departure procedure carefully and keep it to hand.
Display the airways on your MFD (if equipped)
Confess: Can you give me an initial vector? Can you give me a turn onto the airway, I’m having some trouble setting up the fixes, etc. etc.
Then press Direct on the Garmin, put SLI in as the way point, cursor down to the CRS (course) field and enter the TO radial for that airway (238 in this example) and then activate.
I like your method better than the way I would have done it (OBS and dial).
Assume ATC says “fly heading 280 and join Victor 8 to Seal Beach”. You would then twist HDG 280 and let the AP fly. Then press Direct on the Garmin, put SLI in as the way point, cursor down to the CRS (course) field and enter the TO radial for that airway (238 in this example) and then activate. Your active leg will now be V8 to SLI. Press HDG-NAV and off you go. Make sure you enter the TO radial and not the FROM.
And if SLI is in your flight plan, but the new course (i.e. airway) to it isn’t the one you have in the flight plan, you can press Direct To, cursor over to the FPL field and select SLI, then move to the CRS field as you described and enter the inverse of the airway radial.
Unfortunately, the Direct To NRST field only has nearest airports, but that one’s handy for painting the extended runway centerline (well, airport centerline) without having to twiddle the HSI (or PFD [:)] ) in OBS mode.
Jerry:
The NOAA charts show the same inforamtion as well. Each grid has the highest obstruction depicted. Stay above that altitude and you are OK. VFR charts NOT needed to insure obstacle clearance.
You’ve definitely gone native. What sounds ‘busy but nice’ to a New Yorker sounds like getting your head ripped off to us laid back Californians!
Years ago I worked for a company that integrated an east-coast divison with a west-coast one. Trying to meld the two cultures, they drew up an East-West translation dictionary. I remember one item – Eastern “f**k you” = Western “have a nice day”.
That’s right JIm. Now I have developed a mental block on this one. The MEA gives you at least 1000 feet separation from obstacles and 2000 feet in mountain areas. What I cannot remember is whether the OROCA gives the same thing or whether those numbers are the actual height of the highest obctacles in that quadrant. Do you know which it is?
The big block numbers on the NOAA charts are the OROCA altitudes which provide either 1000 or 2000 foot clearance.
Note that similar numbers on sectional charts are the altitude of the highest obstruction and do not provide obstacle clearance.
MEA gives you obstacle clearance and primary navigation reception, MOCA (if provided) is just the obstacle clearance. ORCA only gives you obstacle clearance (as defined by IFR, 1000 or 2000 above highest obstacle in grid).
Thanks Lou. That was the source of my confusion. The Sectionals show obstacle height but the IFR charts give 1000 feet clearance on the OROCA. Sounds good. So we would not be skimming the tops of the trees flying at OROCA altitudes.
One thing I do before flying in busy areas like LA is to highlight the airway numbers and local waypoints on my IFR charts. I use one color ( tape) for my filed route and another color to highlight other identifiers of navaids, and routes in the area. This helps me quickly go over them all without missing any. Finding them without highlights is much more difficult at 180 KIAS over LA!
I use one color ( tape) for my filed route and another color to highlight other identifiers of navaids, and routes in the area.
I’ve been using “Erasable Chart Highlighter Pens” to mark routes and fixes on my charts. These work just great, and they quickly and easily erase using the other end of the pen. Click here to buy these. $2.00 each.
I agree with your tips, especially having the VORs tuned. However, I contend that with practice using the 430 to fly Victor airways is not at all difficult and has the advantage of showing your active course on the MFD. Of course, if the GPS goes out it is nice to have the VOR as a backup.
