AdamFrisch

After not having flown for 14 years, I've now gotten back into it and revalidated my license. However, even after rereading the theoretical stuff, there are some things I keep missing or don't understand. All very random, so best suited for simmered down couchies with broad knowledge.

1. Oxygen. In the US it's mandatory above 12500ft, whereas in Europe it seems to be 10.000ft. Is this European one a recommended altitude for oxygen, or a mandatory one?

2. Transponder. What exactly is the difference between a Mode C and a Mode S transponder?

3. Transponders abroad. Was it in the Netherlands that one could not fly without a Mode S transponder? Any other countries that have similar rules?

4. Weather. From when I read TAF's and METAR's, I can't find any references to the tops of the cloud bases, only the ceilings. Where do people get this info?

5. NOTAMs. Where do I find them for, let's say, international flight planning? And is there a way of plotting a route visually and then have all the relevant Notams that could affect pop up? If not, how do you sift through all of that to find relevant stuff pertaining to your track/route?

6a. Min altitude. Back in the days when I did it in Sweden it used to be 500ft AGL was the lowest altitude one could fly at except for approaches and takeoffs. I couldn't see any reference to that in my new PPL theory book. What's the minimum alt?

6b. Min altitude at airport. This question only relevant if min altitude is 500ft AGL (see above). At Lydd they won't let anyone take-off VFR when the cloud base is below 1000ft. Now, if the min altitude is 500ft AGL allowable, then why do they impose this? And is it up to each airport to set their own minima (not saying it would be prudent to takeoff in 500ft of cloud base, just wondering about the legalities)?

7. What to call them? When you approach, let's say, London TMA and call them up to get a clearance - how do you know what to call them? How do you know it's Control and not Radar, or Approach? All it says is London TMA or CTA or something on the map.

8. Permit To Fly. What's the difference between a permit to fly and C of A in practical terms? Can you fly abroad with a permit to fly aircraft (seem to remember that Jersey wouldn't allow PtF aircraft)?

9. Transponder settings. It seems like most instructors want you to put the transponder to STBY after checks, and then switch it to ALT before you leave earth. Why is that? Why can't one just leave it in ALT all the time?

Thanks.

Fuji Abound

I will have a go - dont quote me

1. FL130 in a G reg, but this is not mandatory,
2. At its simplest aircraft can be individually interrogated, which is not possible with mode C. The response will include the aircrafts unique identity. Enhanced mode S also provides other flight parameters (speed, heading etc., but rarely applicable to units installed in GA aircraft.
3. Yes, the position is mixed across Europe and some areas even require mode S to be turned off now.
4. Correct. There are few reliable sources. Many use meteoblue which provides a pretty good service and form 215/415 is helpful as well as SigWx
5. NATS provides route briefs - you need to register which is free. There are various third party offerings such as Notamplot - some are free, some charge. Do a search on here - there is a good route planning software which a forumite has developed.
6a. No changes there unless clear of everything - 50 feet over the sea would be strictly legal as long as their are no swimmers or divers just below the surface or 500 foot away laterally,
6b. I have never heard that one.
7. Are you talking about coming off airways or in airways. I assume the former?
8. Any country can give permission to a permit aircraft if they wish and most do. Broadly permit aicraft are certified in a different way and to a different standard.
9. To avoid your position being displayed to other aircraft with TAS while not air borne. Many more recent units will suppress their squawk until the aircraft is airborne even if left switched on with Alt.

All of these answers could be expanded greatly. I have had a go from memory so more than happy to be corrected.

Mark1234

6a) 500 generally, 1000 above built up areas, plus lateral limits etc. Pick up an air law book - that's where all this is covered, or look online for rule 5.
6b) What's the circuit alt - that might be a good clue Otherwise I'm not 100% sure but I think there'd be a minimum ceiling for VMC - I'd not takeoff under 500ft ceiling's VFR
7) What you call them depends on who you're talking to. I don't know who you'd call for the london TMA, but it's class A, so no VFR anyway!
9) Because you don't really want A/c on the ground producing transponder returns that confuse the radar picture.

IO540

European regs for what one might call "equipment carriage" are listed in each country's AIP, and the full matrix is going to be a dogs dinner.

In the UK, the ANO now has some stuff on oxygen. Look here and search for "oxygen". It's there. I think this reg is current.
Gosh, a potentially long explanation. A mode S one transmits a 24-bit number which links (via a database) to the aircraft reg. In a high end (non GA generally) installation it can also transmit stuff like autopilot settings.

VFR or IFR? For IFR, a mode S is a must, everywhere, more or less. VFR has various examptions but they are so complicated that unless you just bimble you may as well get one.

Oh dear, another one I will sedn you a PM.

Here. To cut out the crap, you use your head. It is pretty easy. Nearly all notams are irrelevant (like, telling you that 3 RAF planes will be flying awfully fast somewhere...)
Same here, 500ft spacing to people, houses, etc. 1000ft above towns, plus you (if SE) must be able to glide clear.

ATC control things and they can do what they like. If you think about it, a departure in OVC006 could be legal so how will they stop you? At a NON ATC airport they can't stop the movement anyway.

Airports in CAS (Class D in the UK, basically) have a min cloudbase for VFR, generally 1200-1500ft but it varies. This is ICAO (1500ft I think).

The LTMA is Class A and is therefore no go for VFR. You can't go there IFR either except on a Eurocontrol route, which is altogether different (FL100 min, generally). Big subject...
PTF is national and has no default international flight privileges. Also no IFR.
You can leave it on ALT, but if you do it at a radar airport they might not want so many returns. OTOH at some (Prague is one I think) they actually want you to leave it on.... A good point.

Halfbaked_Boy

'Tops of the cloud bases' and 'ceiling' means the same thing. I.e. the base of the cloud, which is the accurate one and what is published in TAFs and METARs!

Cloudtops on the other hand, are one of the most difficult things in meteorology to predict, and there are really only two 'accurate' methods of knowing this information -

1) Aircraft observation

and

2) Skew-T diagrams (if you're not familiar, I'd suggest reading up on them, they can be very useful if you have more than just a passing interest in Meteorology).

I may have missed something, so anybody please feel free to add to this!

BackPacker

Actually I think a mode-S transmit the 24-bit unique ICAO aircraft identification (an impossibly long number which nobody uses) *in addition to* the flight ID. (Plus the good old mode A 4-digit code and mode C pressure altitude.) The flight ID for GA is generally the callsign (G-ABCD) but for airliners is their flight number, BA1234 for instance. The GA transponders I know about allow you to change the flight ID yourself without any special equipment, access passwords or anything. In fact, some are too easy to change, and our club has actually send out a warning not to do that because it confuses ATC.

In the early days of mode-S, people were supposedly flying around with flight IDs set to "JESUS" and similar things, greatly confusing ATC when they got their first mode-S scopes.

So I don't think the link works through a database, but rather direct. Although obviously there is a database with all the aircrafts details, including the callsign as painted on the fuselage and the ICAO 24-bit ID. In the UK this database is called G-INFO and maintained by the CAA.

Whether mode-S is required in a country (and if so, under what conditions, at what levels and such) can be found in the AIP of each country. You can find most AIPs at the Eurocontrol site: EUROCONTROL - The European AIS Database: Introduction to EAD Basic - Home. Need to register, work your way through a number of menus and eventually look for an application called PAMS light. Netherlands looks to be getting ahead the rest of Europe in making mode-S mandatory, but you can still fly in the Netherlands without mode-S. You either have to stay below 1200 ft (which is no significant problem in a country that's below sea level for a large part anyway) or have to get a waiver in advance.

As IO540 said, if you do any significant touring, mode S is a must for all practical purposes. Planning a significant VFR flight throughout Europe without mode S is a major headache. And while you're at it, install an ELT too, for the same reasons.

That Eurocontrol site also does NOTAMs for the whole of Europe, by the way.

AdamFrisch

Thanks for the responses, very helpful.

As for knowing what to call them and who, let's just assume a hypothetical flight from Headcorn to Elstree. If I wanted to ask for a clearance through the London City CTA (as it's marked on the map), then who do I call up? Thames Radar? City Approach? London City? How do you know?

Another one is all the MATZ's. They have no name. It just says MATZ on the map or CMATZ. I can think of at least one MATZ that has three different fields in it, so how do you know what to call them?

IO540

You can get a clearance through the LCY Class D but doing that flight in a single engine plane would not be too wise as you can't comply with the glide clear rule.

The story on this one has varied and it has been claimed that the CAA has ruled on it in the manner above. I don't have a reference though.

But yes it would be Thames Radar. For any Class D transit you call up the controlling authority, whose frequency is marked up on the VFR chart. For the Southampton piece you call up 120.225, or 119.475. These are on the chart.

A MATZ is not controlled airspace. It is "polite" to call up somebody - usually the nearest radar unit.

Fuji Abound

Thats a good question, to which I dont know the precise answer.

Southampton and Bournemouth, Birmingham, City and Gatwick all have class D veils, and I think the veil is protected by Birmingham approach, City radar, Gatwick director and Solent radar. The flight guide will tell you and the notes bottom left of the CAA chart can be helpful, but beyond that how you would know from looking only at the map I dont know.

Calling xyz radar and you will not go far wrong. There are those who call them all sorts of things but mostly in anger when they refuse a clearance.

Fuji Abound

PS - as IO says you might be chancing your arm going overhead City to Elstree. The old route was up the Lea valley and very convenient it was but I tend to only go that way in a twin for the reasons IO gave. Cut the corner overhead Damyns positioning somewhat further up the Lea should work fine, just remember the glide clear rule.

AdamFrisch

Well, the higher they can clear me, the further I can glide

IO540

Not really, because the base of Class A is 2500ft around LCY.

The only way to get higher in that area is IFR and then there are transit possibilities at/above about FL100.

To meet the glide clear rule over London generally, you need to be around FL150, I think.

But I see no evidence of IFR capability here, so Class A is out.

Captain Stable

Do the boys in blue have different terminology from civvy pilots wrt cloudbase?

Years ago a girlfriend of mine had a Group Captain for a father and I remember mentioning "cloudbase" to him and being corrected by him saying "ceiling".

tmmorris

MATZ frequencies are on the map - just underneath the word MATZ! - but they don't always tell you who the frequency is (e.g. Mildenhall/Lakenheath CMATZ just says 'CMATZ 128.9', though the NOTAM activated bit for Honington does say 'MAZT NOTAM Activated Lakenheath 128.9' which is more helpful).

Default callsign for a MATZ is 'Zone' e.g. Lakenheath Zone.

Tim

BackPacker

This sort of information can easily be found in any flight guide. Or in the AIP of course.

IO540

Almost nobody reads the AIP

Private pilots tend to read flight guides (Pooleys, in the UK).

Serious private pilots (however you define that?) tend to use airport data in flight planning software e.g. Navbox or Jepp (which is in turn lifted from the AIPs, or other flight planning software).

Quasi commercial pilots use Jepp, plus airport directories like ACUKWIK, with heavy reliance on handling agents, etc.

Real commercial pilots don't read anything because they have an OPS department

I think pilots in N Europe are spoilt because their AIPs are reasonably accurate, but once you get to Africa (i.e. anywhere south of the Pyrenees or the Alps) the accuracy goes way down - but if you do something wrong, the national CAA is ever so quick to point you to some page in their AIP

Fuji Abound

I find the only times I ever really consult the AIPs is when going somewhere new outside the UK.

For example, for France the AIP is usually quite helpful and I find the contact numbers are generally up to day as well as the op. specific information. This also saves having to maintain flight guides for a whole load of different countries.

BEagle

Whatever is a Class 'D' veil? I've never heard of that term in the UK.

Fuji Abound

It is a little American init - sorry.

You know what I mean.

Mind you a see the gliders are all talking about the dreadful veil around Stansted - anyone would think they couldnt fit transponders.

gasax

SoCal has a bit of a point - but really it highlights the whole 'portacabin' mentality of 'flight training' in the UK.

Mode S - how many club aircraft have one? Less than 5%?

Oxygen? How many hours building instructors have ever been over 6000'?

Flying abroad? Unles you are on the south coast not one will have been outside of 200 miles of their home field.

The tops of clouds? Who ever goes there? (me included to be fair!)

What to call them? - never go there so no need!

Permit to fly? - what is one of those?

Minimum altitude - they should be able to answer and in the books.

So perhaps not surprising that the poster does not know the answers. Interestingly the momst experience instructor at my club only went places in the 1980s - his 'information' is truly interesting.......