This is going to sound really odd, but can anyone actually fly a plane on here? I some info off an aerodrome chart, but dont know what some of it means, so if anyone can read the pilots approach procedures and aerodrome charts let me know, i need help!

I did the the full PPL course but when it was time to begin actualy flying lessons I gave up after 2 due to the cost. Do you have the charts in PDF format? Send them over or PM me, maybe I can help you out.

Otherwise I think Mase on here was learning to fly too but I have't seen him around for a while...

Can you get it hosted somewhere? I'll have a look.

Aha, thats what we like to hear! Be warned tho, now i know you guys can help i might be bugging you from time to time now!

Right, below is the image for Liverpool airport (John Lennon Airport)



I have circled the main bits i am interested in. The top circle shows two heights. The first is the elevation above mean sea level (179ft). But elevation of what? As the airport is only about 15-20m amsl, which is ~50-65ft. The the second height is heights above AD, but what is AD?

The second circle then shows the little mountain symbols, and then those heights. Now does that mean that that is the location of the highest point i.e. the terminal building is the tallest obsticle.

Now lastly, i have circled an ILS aerial, which again has those heights. But in the textual aerodrome data it lists all the obsticles that are in and around the airport. The ILS aerial is listed as being a height obstruction, but then the bit thats highlighted in the second circle is clearly higher than the ILS aerial so why isnt that listed as a height obstruction. So thats whats really confusing me.

I hope i'm making sense, please help

Hi Chris... Firstly the elevation of the airfield is not indicated in your top highlight but on the top border, immediately to the right of the coordinates - (ELEV 80FT). This corresponds more closely with your expected value (20-25 Mt).

The values in your oval hightlighting are both highest obstacles elevations (Note "Elevations" - plural). One is expressed in feet AMSL and the other in feet above AD. I'm not 100% sure on this but I think AD stands for Aerodrome in this context. Usually you also have this acronim for "Airworthiness Directive" but in this case it clearly does not apply. Notice also that hights (above ground) are expressed as values in brackets.

To double check, just add up everything:

AD elevation: 80 FT + Heights in feet above AD: (99 FT) = 179 FT "Elevations" AMSL.

The terminal building is indeed the highest obstacle listed.
Not sure what you mean by the "second bit" but I guess you are referring to the "GP (47)" symbol. The whole ILS 127 / GP(47) is in fact a single obstacle indicator. GP stands for "glide path". The localizer antenna is located elsewhere (inline with runway). So the indication again is repeated: 127 ft AMSL, or 47 FT AGL. Again... 80+47=127, so it all adds up.

Hope this helps.

Ahhhh, now that makes sense! Thats cleared it right up. Thats great Nick, really apreciate you're help, i can get on with some work now, thanks!

What Nick said was correct. AD does stand for Aerodrome.

The obstuction symbol also shows if it is lit. You can see the terminal building isn't but the ILS GP is.

I only know about general aviation. When landing you'd normally have your altimeter set to show your height above the ground (zero on the ground) so would need to know the height of the obstuction in the brackets.

When taking off you would normally set your altimeter to show altitude above see level. You would then need to know the top figure listed with the obstruction.

If the terminal is actually higher than the ILS aerial, why is it not lit, and why is it not listed as an obstacle in the textual data whereas the ILS is?!?

I'm not sure why thy the ILS aerial is lit and the terminal building isn't. I know obstuctions over 500ft above ground level have to be lit but below that light they may or may not be lit.

At night IFR or SVFR is allowed. If you're in unclassifed airspace this just means you've got to comply with the quadrantal and minimum height rules. You can't fly at night on a basic PPL, you need a night rating. This could be done at the same time as your PPL though.

So why isnt the terminal listed as an obstical in the textual data when the ILS aerial is? The textual obstacle table is show below....

A couple of guesses.
It may not be lit because it's significantly far enough away from the runway not to need it whereas the ILS beacon is on the grass next to the main strip.

Or, the lighting symbol means 'special' lighting (a specific colour or strobing) other than just general building stuff (which the tower might have anyway).

A very odd request from a very odd person