Fast station approach

Certainly on the open sections between East Finchley and High Barnett - where you can measure speeds and acceleration with a GPS - the 1995 TS does not sparkle in any direction irrespective of gradients etc. The GPS reckons Jubilee line 1996 TS stock performs better on it's open section of line. I don't know 1995 vs 1996 TS specs are and how much the stock is capped by. It is clear that the newer sections of Jubilee line I. E Waterloo to Stratford, allows higher speeds than the 'old' Baker Street to Green Park section, and the even older Baker Street to Finchley Road Ex Bakerloo Line tube lines.

Accelerometer only measures g-force, so you can only compute speed based on accelerometer data, vehicle weight, rolling resistance etc. Pmly good if you are on a level track or known constant gradient. While
GPS accuracy is subject to a number of conditions - I wouldnt trust a phone built in GPS - there are GPS devices capable of recording speed accurately even in a moving train carriage. The point is, whatever device you use, you are going to record data that can be compared. And going back on topic, GPS data that i have seen confirms that for whatever reason, the jubilee line trains seem to be driven faster than trains on the northern line , acceleration and top speed - even though the tube stock in use is very similar. What is also clear is how much more consistent the station start to stop times are on ATO lines, especially the underground sections.

What are the power and weight specs for 1995 / 1996 TS compared to 67 and 72 TS?

Charlie, I know you've delved into this to the nth degree and forgive me for being dense, but how does a train with around 60% more power fail to accelerate faster than the other type according to all these other people? It doesn't make sense to me.

;D Ah.....I see. Anyway, thank-you for the speediest response I've ever had on any forum anywhere. You must be a 72 stock old son.

Okay, so you flip your accelerometer onto it's side! Now it is recording massiveg-force and yet it is sat on a table going nowhere! How fast is it going??? do the maths! See the problem with accelerometers? Meanwhile my phone gps - is recording 0 mph! Which is most accurate?

No bombshell because in this case we are talking about velocity, acceleration and braking to / from the trains service speed! Personally I use a device that combines gps and accelerometer data. Yes gps can be laggy, depending on the chipset used. A bit like computers. The gps chipsets used in mobile phones, for example, are compromised because they are designed to consume very low power and fit on a chipset along with the other mobile phone circuitry, and of course designed to keep cost down. However you can buy high accuracy, higher performing chipsets, and they can cost into the thousands, before you build a device around them. Check out Racelogic V Box and Race-technology websites! In fact both companies produce devices that integrate accelerometer data and GPS. Go a step further and you can buy GPS devices that integrate GPS and inertial navigation data, which is even more accurate, but will cost tens of thousands of pounds! Having extensively researched this area and tested countless devices I am happy with the accuracy of my GPS speed measurement device, and at the moment I am not aware of any accelerometer only devices that can measure and record the velocity of a moving vehicle over long distances with the consistency and ease of use as a GPS device. Most track day drivers have now shifted to GPS from accelerometer devices as a result!

Great. Going back on topic, Please, when you get time, record some acceleration and deceleration rates pm the diffetent types of rolling stock and post them here on the forum for us.

Depends on which line, as those with 8-car trains have a few extra metres to play with compared to those with 6-car trains.

On the Northern trains approach typical platforms at anything between 25-35 mph depending on the individual Train Operator. Certain favourable platforms, e.g. Highgate southbound (9 car platform), Brent Cross southbound, Woodside Park northbound (both uphill approaches) can be entered a bit more, Brent Cross southbound platform ramp can be hit at 40 mph with braking to spare even with wet rails.

On lines such as the Central, Victoria and Met with the longer trains, platform approaches at 35-40 mph are more typical.

TBTC on the Jubilee seems more variable, but I've seen some 40 mph platform entries on a few occasions.

I suspect having more powered axles is an advantage on 92 TS than the extra outright power. Also maximum starting effort per motor is a variable along with how much power the computers are programmed to apply through the acceleration process. For example the main line class 87 locks could be accelerated much harder cos drivers could control actual power delivery, I. E pushing ammeters into the yellow zones. Whereas class 90 with virtually same motors have computer controlled power delivery! Surprised to see that some of the fastest recorded start to stop station times on the central line underground sections are still in the hands of 1962 TS!!

I think there may have been a touch if overspeeding plus very late braking. I will try to record some times on an early morning train when there is more juice available and less chance of line congestion.

Ah yes!! Wheelslip... Remember it fondly on the 62's.
Picadilly 1973 TS always seems prone to it too especially on restart.

09ts tends to brake a fair bit before the station, 92ts seems to apply the brake before the station with full breaking only just as it arrives in the platform. Deep level only...outside the braking profiles are less harsh.

The Jubilee will get quicker when the new timetable comes in.