Several months ago there was a NOTAM for EDNY (Friedrichshafen) that they are changing the DH and DA for the ILS of at least one of the runways (unfortunately I don’t have it any more to quote it exactly). After the last Jeppesen update I checked the current chart and it is still the one from 2013 with the old MDA:
So I decided to check the chart from Eurocontrol and it looks like this:
This raises two questions for me:
However Jeppesen is not updated.
Because it is not necessary!
So when does Jeppesen update their charts?
As soon as possible in most cases. Sometimes within a week. If that is not possible, they will send a “database alert” mail to their registered users.
How legal is it to fly with different charts from different issuers?
As long as those charts belong to a current subscrpition there should be no issues with legality!
The Eurocontrol chart does not have DH or DA at all.
Actually it is a German AIP chart, Eurocontrol does not issue it’s own charts. Many national AIP charts have no decision altitude, because this is an operator specific thing. Instead they give the OCA, which is a physical property that is equal for everybody. To that, a company/operator specific margin must be added to get your personal DA. However, for a CAT I ILS approach, DA must never be smaller than 200ft. Jeppesen adds some standard margin which is acceptable to most operators, therefore they can live with Jeppesen computed decision altitudes.
In case of this last chart revision of EDNY (the changes were indeed related to OCA as can be seen from the AIP chart) OCA + (Jeppesen) margin remained below 200ft, so Jeppesen did not need to change their chart.
More details and a better explanation can be found here: Minima made easy
Great answer, thanks @what_next.
I understand operators calculate their own margins (as well as contingency procedures) but how do the GA pilots flying privately go about these?
Vladimir wrote:
…but how do the GA pilots flying privately go about these?
That’s completely up to you, add the safety margin that you are comfortable with. If you found out that when flying single-pilot IFR without autopilot typically makes you lose 50ft during the time you look for the runway, add 50ft. If you don’t lose any altitude while looking out (like Chuck Yeager and Neil Armstrong ) add nothing.
However you must not set your decision height lower than 200ft for an ILS and 350ft for a non-precision approach. These are legal “hard limits”.
In connection with this thread in which we discussed exam relevance, this topic is definitely not described well in the books. And it is so easy – three short paragraphs from a person who knows what he is talking about.
It is a scandal that the national AIP charts do not in most cases have an MDH/DH on them.
This is one big reason why most of the world uses Jeppesen charts.
Unfortunately Jepps are very expensive…
I wouldn’t call it a scandal – the two ‘products’ are presenting different information. Personally I can remember that the hard limits are 200 and 350ft and I take things from there. Furthermore, how can Jep (or anyone else) tell me what DA/DH to use? There may be a plethora of reasons for an enhanced DA/DH. For example, the DA42 needs a 50ft fudge factor due to altimeter inaccuracies.
PS. This is actually one reason why QFE makes life easier.
PPS. I use Jep mostly.
Peter wrote:
Unfortunately Jepps are very expensive…
But you can share one subscription between four pilots and then it’s something like 40 Euros per month. Cancel you Sky TV subscription and get Jeppesen instead, much more value for money
the DA42 needs a 50ft fudge factor due to altimeter inaccuracies.
What does the FAA approved POH say?
My FAA one doesn’t have a correction factor, and the CAA examiner I had for the JAA IR agreed with me that no 50ft add-on is required.
Incidentally, an instructor/examiner working for a well known FTO told me that the 50ft add-on was invented by the FTO business to increase first time IR pass rates. Apparently, the standard TSO spec altimeter error is already allowed for in the IAP design.
But you can share one subscription between four pilots and then it’s something like 40 Euros per month. Cancel you Sky TV subscription and get Jeppesen instead,
The four-device sub for “political Europe” is about €2k/year, so yes you are right They also now do a one-device sub for about €900/year, which works out more expensive!
much more value for money
Agree 100% – most TV is trash nowadays But I would not pay for Sky anyway.
Peter wrote:
They also now do a one-device sub for about €900/year, which works out more expensive!
Actually it is €535/year for (what they call) Europe which comes approximately to the same per device as the 2k they were requesting before. I think the 4-licenses subscription is not available any more on the web site, you have to request it explicitly on the phone. The bad thing is that if you want to have a backup device (always flying with both, so actually always using only one) you have to pay two subscriptions.