I’m wondering if it is possible to call up the local approach facility and ask them for flight following even if you are just doing sightseeing or something. Do you need to tell them your intended route, altitude, and destination? How would you ask them for flight following without a specific destination?
In order for a TRACON or tower to enter you in for long-distance flight following (which in my lexicon is the only type of "flight following," though the official documentation doesn't differentiate) we need to create what is essentially a limited-information IFR flight plan for you. The minimum required information to enter this plan is your callsign, destination, and type. A cruising altitude is not strictly necessary but leaving it out can mess up the transfer of the tag down the line, so you should always give it.
If you are not going to be handed off from facility to facility, but will be remaining within the airspace controlled by one single facility, we can enter you in for an isolated "local" code that does not interface with the flight data computer at the center. Route of flight, altitude and aircraft type are still good things for the controller to know, but the minimum information necessary to enter you into the system is nothing more than a callsign.
A Center controller might not have the option of entering you in for a "local" code so they might need a rough destination no matter what. I'm not experienced with the Center systems.
You should say something along the lines of "request traffic advisories in the north practice area" or "traffic advisories for a skyline tour" or "transit the Charlie at 3500" or "aerial survey at 4700" or whatever it is you're looking to do.
You call up ATC, tell them that you are out sight-seeing and would like flight following and traffic advisories. On a workload permitting basis ATC would provide the service.
Here is an excerpt from the FAA Air Traffic Control Handbook:
Section 6. Basic Radar Service to VFR Aircraft- Terminal
a. Basic radar services for VFR aircraft must include:
- Safety alerts.
- Traffic advisories.
This is a very common request and depending on the location there should be very little difficulty in receiving this service.
The excerpt above, from the FAA Air Traffic Control Handbook, describes a Terminal function, which doesn't apply to Centers. Our rules for VFR services, however, are similar.
A Center controller would have the option of providing services on a workload basis. Keep in mind that there are factors besides workload, such as frequency and radar coverage issues. We get frequent requests from photo missions that fly grid patterns (which we may not have access to, for whatever reason), round robin, cross country, aircraft checking on cattle herds and oil pipelines, and yes, sightseers. We will need your planned route of flight to be able to provide the best services, even if it's something like "We plan to fly up to Devil's Tower, then over to Rushmore, then back to Chadron". (A very nice scenic flight, BTW)
Our VFR services include traffic, terrain, and airspace advisories, as well as displayed weather along your planned route. We also have access to AIRMET information for the sector.
In my opinion, calling up an ATC facility for flight following is cheap insurance.
In the Center, we can use a local code, or, just leave you on the VFR squawk, if you're staying in a particular sector.
In ZDV, sectors are pretty large, and that Chadron..Devils Tower..Mt. Rushmore..Chadron round robin is in one sector, a sector which is roughly 180 NM wide, and 230 NM tall. I could flight follow you from Scottsbluff, NE to Lusk WY, then to Newcastle, WY, to Philip, SD (with a 70 mile transition to Ellsworth AFB control), to Valentine, NE, to Ainsworth, NE, and back to Scottsbluff. That's nearly 700 nautical miles, and well within the sector boundaries the entire time.
Would I use a handwritten flight strip and not ask about your aircraft, if I knew you were going to round robin in my sector for 5 hours in a Skyhawk? No way.
You'd get a standard squawk, and I'd ask you for your aircraft type, qualifier, and planned route, and probably some particulars as you neared airports in your VFR plan. (planning touch-and-gos?, fuel stops?, diverting a few miles to buzz a neighbor ?(don't tell US about THAT!))
Everything else aside, CALL US! You've paid for the service in fuel taxes, licensing, certification, and a myriad of other levies that I have no idea about. The worst that can happen is the controller is too busy. In the US, if the service CAN be provided (based on workload, radar, etc.), it SHALL be provided.