departure procedures

[frascapilot]

Got a question on IFR departure procedures. I use Jepps. Occassionally there are obstacle departure procedures on the back of the airport diagram. Then there may be what was formerly called a SID in a separate chart---believe now it's now called an Instrument Departure Procedure. In addition, ATC will give you their own vectors. In my thinking, these are 3 different scenarios of flying the departure. Am I correct that all three guarantee you the same thing being, 35 ft above end of runway a climb straight to 400. turn in any of the 3 ways, 200 fpnm of clearance to another altitude (MEA, MSA etc) that guarantees clearance. Please correct any incorrect numbers...... In the ATC example, you will be above the "diverse vector area", which guarantees the same as the others. Referencing AIM 5-2-6.

 

[tarp]

1. There are no guarantees except the performance of your airplane on the given day. The 5-2-6 numbers in the AIM coincide with the FAR 25 transport category aircraft requirements that in an engine failure will reach 35 ft by the end of the runway and turn 400 ft above the ground climbing at 200FPNM, etc. etc.

If you are in a single engine aircraft and the engine fails, I doubt you are guaranteed anything.

2. The old Obstacle Departure Procedures that were either the "T" in the front of the NOS charts or the "text" on the Jepp charts were designed to keep you away from obstacles. In some cases they referred to a requirement to climb at some specified value that was greater than the "standard" 200FPNM. i.e. if an ODP needed 275FPNM to clear some obstacle in the plane ahead, it would be specified. You would use the gradient charts to see if the FPM (feet per minute) and performance of your airplane on the given day would be better than the FPNM that was required for the procedure.

Take for example, Cumberland, MD (CBE) where a departure needs 660FPNM to 3400 to clear the relatively steep mountain sides close to the runway. Let's say now that I have an airplane that climbs at 120KTS but is also loaded to the max on a 99F degree day. The translation table says I need 1300+ FPM rate of climb out of this plane. Can I do it??? Go to the POH!

3. ATC has only one requirement when they decide to RADAR vector you on a departure (one requirement with regards to the ground that is). If they RADAR vector instead of a departure procedure, they must provide 1000 ft clearance over the highest obstacle within 3 miles while you are operating under a Minimum Altitude. (There's a sub-note that this is only if you are within 40 miles of the RADAR antenna.) That may be why it seems that ATC is a little slow to say the words "Radar Contact" on departure.

I gather that the words "Fly runway heading" or a turn to a certain heading after departure taking into account a normal 200FPNM climb should keep you clear of obstacles until you are radar identified, but that responsibility is on your shoulders, not ATC.

The PIC has the ability to refuse the departure clearance if the plane cannot meet the criteria. You have the option of choosing a different runway or waiting until weather conditions favor your aircraft. Guarantees - the only ones I know are the sun will rise in the morning and the IRS wants to be paid every April.

 

[Vector4fun]

Ummmm,

ATC *may* vector a departure less than 1000' above the ground/obstruction under certain circumstances. Per the 7110.65:


5-6-3. VECTORS BELOW MINIMUM ALTITUDE

Except in en route automated environments in areas where more than 3 miles separation minima is required, you may vector a departing IFR aircraft, or one executing a missed approach, within 40 miles of the antenna and before it reaches the minimum altitude for IFR operations if separation from prominent obstructions shown on the radar scope is applied in accordance with the following:

a. If the flight path is 3 miles or more from the obstruction and the aircraft is climbing to an altitude at least 1,000 feet above the obstruction, vector the aircraft to maintain at least 3 miles separation from the obstruction until the aircraft reports leaving an altitude above the obstruction.

b. If the flight path is less than 3 miles from the obstruction, and the aircraft is climbing to an altitude at least 1,000 feet above the obstruction, vector the aircraft to increase lateral separation from the obstruction until the 3 mile minimum is achieved or until the aircraft reports leaving an altitude above the obstruction.

c. At those locations where diverse vector areas (DVA) have been established, terminal radar facilities may vector aircraft below the MVA/MIA within those areas and along those routes described in facility directives.

==========================================

What that means is, for example, Terminal ATC may turn you toward a tower with a top of 1500' msl as soon as you're out of 1600', so long as you are climbing to an assigned altitude of at least 2500', (with some restrictions.)

Also, where a DVA has been established, and facility directies exist, a terminal departure controller may vector a departure below the MVA. The pilot must inform ATC if he/she can't manage the 200 FPNM minimum.....

 

[Lufthansa]

So if you accept a heading from the tower after departure in lieu of an assigned Departure Procedure, who's responsibility is it to maintain obstacle clearance?

 

[avbug]

You are. ATC becomes responsible once vectors are issued.

 

[Lufthansa]

How is it a heading from the tower is not an "vector from ATC"?

Not trying to be arguementative, just trying to iron out some wrinkles in my thinking.

 

[mainah]

Responsibility

I always try to stick with the following joke:

What does a pilot screw up have in common with a controller screw up?

The pilot dies.

Always double check altitudes and headings given by ATC.