Heathrow and altitude fix at 6,000ft?

[Ari]

Flew out of Heathrow for the first time this week (remarkably. Is usually Gatwick or Standstead). Anyway, we take off, all good, suddenly power winds off and we stop climbing, help..!

We bump along at 6,000ft (airplane has those monitors that show position and height/speed/air temp) with me panicking that something dreadful has happened then after a couple of mins, power back on and up we go.

Looking at the map thing, the power seemed to go back on more or less level with the M25. So is there something that means planes climb to six thousand and hold at that till they clear London? And if not, any ideas why?

[Ari]

Chuck328 said:

So, flying out of Gatwick or 'Standstead' you have never noticed that you will usually stop climbing shortly after take off at these airports? NO you probably wouldn't notice without a map thing.

Busy London airspace often means an unrestricted climb to altitude is often impossible. Seriously, if that makes you panic, stick to the train...

It's never happened (to me) coming out of Gatwick or Stansted (well done you on pointing out a spelling error!! Did you know you wrote "often" twice in the same sentence?) Map or no map, its a pretty obvious reduction of power. Normally they power back a bit after a minute or two, but the plane is still obviously climbing. It was the power shutting down and the lack of climb that made me look at the screens not the other way around.

And yes, very nervous flyer but sadly the train doesn't get me where I need to be (at least, not the same day!)

[Ari]

LHRFlightman said:

At 6000 you'll be flying under one of the four stacks. Give me the date and flight number and I'll confirm tomorrow

Ah, that makes sense, thank you. I wondered whether it was some sort of noise or pollution nonsense but it didn't seem very likely.

I'll get the flight number and let you know.

[Ari]

peter tdci said:

If the engines are still running, then it's usually ok! There's also a speed limit below a certain height, so if that was being enforced the change in acceleration would be more noticeable if the aircraft levelled off and maintained its speed at that limit.

Ah yes, that makes sense too, thank you.

[Ari]

magpie215 said:

250 kias below 10,000ft iirc

I don't know what that means...

[Ari]

Ah, ok. Is that a noise reduction thing?

[Ari]

bennyboydurham said:

You'll have been on a SID, or Standard Instrument Departure. In essence, these are standard routings to get traffic from the departure runway to the point at which they continue the journey under their own navigation. Imagine them as slip roads in the sky to the motorway entry point. So, let's say the first point on your flight plan is the navigation beacon at Midhurst VOR in Sussex. Your pilot will be assigned one of the following four SIDs according to whichever runway is in use, punch that into the flight management computer and then after takeoff follow that track, climbing to the heights either as per the chart (3000, 4000 and 6000 feet in the case of the MID4F SID off runway 27R) or will receive instructions from ATC giving him headings and altitudes which over-ride those on the chart. When your pilot gets to the MID beacon he'll be told by ATC to 'resume own navigation' which means the aircraft is cleared along the series of beacons and waypoints that make up the route and will no longer receive directions from ATC, apart from altitude restrictions for other traffic.
In reality aircraft usually fly the first part of the SID and then are given vectors (directions) by ATC. Smaller airfields don't use SIDs at all, and simply direct traffic out away from the airport via radar coverage.

Could you be a little more comprehensive please?

That's brilliant, and very interesting, thank you for that.