In which case you really need a cloudbase of at least 2000 ft. Be aware of where the high ground/obstacles are. If you use Skydemon relate it to the real World by looking out of the window. Never descend towards rising ground! Don't push the boundaries until you have done some instrument flying and you are confident with your ability or lack of it.

I used to know a guy who insisted that on light GA aircraft his personal IFR minimums were VFR.


* This from someone who had thousands of hours.

A safe height is one you have thoroughly planned not some arbitrary number: including surface obstructions such as tall masts and of course high ground, glider and parachute sites, not forgetting notified airspace, "if I need to then I'll divert when I get there". There is little to be gained by having a minimum of 3000ft agl in the UK when you cannot fly that owing to notified airspace or cloud bases which are typically between 2-3000ft and lower.

I find it depressing how poorly navigation is taught: no low level operations training, unplanned diversions skipped. Flight solely by instruments totted up to meet the 2 hours demand but the content almost non-existent, "all that is required is a level 360° turn", no it isn't, the syllabus is detailed and comprehensive but this is ignored.

This is clear of cloud with a visibility of 1500 metres and a minimum height not specified by ICAO.

Very sensible. Especially special VFR conditions (1500 m viz, which is basically one runway length , 500 foot cloudbase) can be quite challenging

Reference to a recent helicopter thread; it is a good idea to know the MSA in the area you are flying in.

If you lose VMC and get into IMC, and a 180° rate one level turn does not get you out of it; you need to have in mind the highest ground or mast that you might be heading towards.

Commercial airliners fly at least 1,000' above MSA unless they are under radar control or are certain of their position and are following published approach or departure tracks. (Certainty of position is confirmed by double or triple IRS, normally with double GPS as well).

For what it's worth, 500' AGL is much too low - give yourself a reasonable safety margin !

Consider the conditions at which you will do a precautionary landing - on the best available ground, not a diversion to an airfield. Then don't get into that situation. Without good instruments and currency a precautionary landing is better than going into IMC.
Consider how close to cloud you will go. Cloud can engulf you.
I have very little experience of flatland flying, and hills help you see changes in cloudbase near you. I'd require a higher cloudbase over flatland.

Excuse my ignorance, what does IRS stand for? The I probably for Inertial?

Sorry; Inertial Reference System; IRS. Nowadays each one uses laser ring gyros rather than mechanical ones, to detect rotations in each axis which can be integrated, (I think), to give velocity and distance travelled in each axis from their starting point.

On Airbus FBW there are three independant units, which are further enhanced with air data inputs and are called ADIRS, three of which are fitted to each Airbus FBW, and combined with two GPS receivers to give very comprehensive position data.

So five systems - not just one system - for position, and even then flying a safety margin above MSA.

Firstly if you look at the original posters other threads it would appear he has experience back home in the States, so may not be a 'new' PPL.

However, I have to correct his statement that SkyDemon does show unflyable conditions. This is from the manual:

This subject came up on the main SD forum recently when someone asked if the feature could report actual cloud bases AGL in dynamic time. Obviously not, as it's only a forecast and entirely dependent on what criteria you pre-load.

As far as what cloud base (AGL) to use in low lying areas of the UK I would suggest a minimum of 1500' unless operating in the higher ground areas of Wales/Lakes/Pennines/Scotland where 'mountain flying rules' are more appropriate. A simple Google search on the subject produces a lot of useful free information.
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Some good suggestions (and some not so good!). However, you should be considering more than just cloud base. In marginal conditions, you need to give yourself even more options than you would perhaps normally plan for. So, at the expense of longer route and more time in the air (which is why most of us fly anyway for enjoyment), minimise hostile terrain and route by more airfields you could divert to if weather deteriorates. Also, practice D&D pan.

If you're flying near London, you won't be able to get above 2500 due to the TMA, so cloud above that is academic unless it's a CB. Further afield, it will depend on the type of weather patterns as to the forecast reliability, the terrain, and the speed of the aircraft you are flying. On many days, at 2300 under the TMA it's quite a choppy ride, so as it's a hobby, you might want to pick days when you can get to 3000 or above, for comfort and safety.
It is better to use the Met Office aviation data than any secondary sources.