HS 125 tech queries please
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HS 125 tech queries please
Just wondring if there is anybody here who is familiar with the HS 125 at all.
If so, a few queries please.
What is the nose wheel steering angle for towing and does the torque link need to be disconnected ( aka the 1-11 ) at all?
ECU...What ground equip is required to drop an engine (Viper series ) and what sort of time scale does this take?
Hyd / Nitrogen replenishment...easy access ?...and how is the hyd.system replenished...Risbridger gun perhaps ?
Cabin door locking mechanism.....four shoot bolts perhaps ?
Flap / flying controls operating system....rods or cables and pulleys?
Ice and rain / airframe anti -ice system....what method(s) are used ?
The questions may seem simplistic from an engineer, but in essence, I am seeking an overview, not a detailed perspective here.
Many thanks.
If so, a few queries please.
What is the nose wheel steering angle for towing and does the torque link need to be disconnected ( aka the 1-11 ) at all?
ECU...What ground equip is required to drop an engine (Viper series ) and what sort of time scale does this take?
Hyd / Nitrogen replenishment...easy access ?...and how is the hyd.system replenished...Risbridger gun perhaps ?
Cabin door locking mechanism.....four shoot bolts perhaps ?
Flap / flying controls operating system....rods or cables and pulleys?
Ice and rain / airframe anti -ice system....what method(s) are used ?
The questions may seem simplistic from an engineer, but in essence, I am seeking an overview, not a detailed perspective here.
Many thanks.
Last edited by Krystal n chips; 14th Jan 2011 at 05:08.
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There will be hundreds of viewers familiar with the 125!
I've based my answers on the 125-700 although with the Viper you may be discussing earlier models, Series1 to 600?
Yes it does have to be disconnected for towing.The Torque link itself is not disconnected there is a vertical steering disconnect pin that connects the torque link sleeve and steering sleeve (a picture explains all). It's very easy. Once disconnected I seem to remember you could go to at least 90 degrees.
Pass on the Viper question! - I think I only changed 2 in 30 years for turbine overheat. I had to persaude the CAA to let me take the type rating oral without doing an engine change.
Hydraulics - Very easy with no sophisticated tooling required. Both Main and Auxilliary have a screw filler cap that when removed you can just pour the fluid in (or unofficially from something like a pressurised bottle). Level indicaters are visual but the pipes often get discoloured.
Hydraulics - Nitrogen quite easy to access and top up but obviously need some tools and connectors
Cabin Door - Not clear what you are talking about. Internal doors or main entrance door? Internal doors are just a simple catch (usually open on a heavy landing). Main entrance door is a plug type and depends on the aircraft model as some early models had the "up and over door" later ones had the combined door and stairs. The door pivots on two hinges. Closing the door lifts the door and drops it into position using spigots and guides 5 altogether if I remenber. Works well but can get out of sequence occasionally.
Flying controls are cables and pulleys
Deicing is by TKS fluid through porous panels on the leading edges - OK but messy.
Even for an overview you might need to be more specific as to which series. Anything more detailed and I'd have to dig out the old books (I pre-date CD's!!)
Hope this helps
Mike Echo
I've based my answers on the 125-700 although with the Viper you may be discussing earlier models, Series1 to 600?
Yes it does have to be disconnected for towing.The Torque link itself is not disconnected there is a vertical steering disconnect pin that connects the torque link sleeve and steering sleeve (a picture explains all). It's very easy. Once disconnected I seem to remember you could go to at least 90 degrees.
Pass on the Viper question! - I think I only changed 2 in 30 years for turbine overheat. I had to persaude the CAA to let me take the type rating oral without doing an engine change.
Hydraulics - Very easy with no sophisticated tooling required. Both Main and Auxilliary have a screw filler cap that when removed you can just pour the fluid in (or unofficially from something like a pressurised bottle). Level indicaters are visual but the pipes often get discoloured.
Hydraulics - Nitrogen quite easy to access and top up but obviously need some tools and connectors
Cabin Door - Not clear what you are talking about. Internal doors or main entrance door? Internal doors are just a simple catch (usually open on a heavy landing). Main entrance door is a plug type and depends on the aircraft model as some early models had the "up and over door" later ones had the combined door and stairs. The door pivots on two hinges. Closing the door lifts the door and drops it into position using spigots and guides 5 altogether if I remenber. Works well but can get out of sequence occasionally.
Flying controls are cables and pulleys
Deicing is by TKS fluid through porous panels on the leading edges - OK but messy.
Even for an overview you might need to be more specific as to which series. Anything more detailed and I'd have to dig out the old books (I pre-date CD's!!)
Hope this helps
Mike Echo
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Mike Echo,
Many thanks for your reply.
You have answered all my questions here..and the one about the ECU has been answered elsewhere.
The query re the door referred to the main cabin entrance door by the way, with my specific interest being as to the form of locking mechanism used. All is now clear however.
The questions were simplistic purely because I needed an overview of the type rather than any specific engineering details ( as such ).
Once again, thanks for your help.
Many thanks for your reply.
You have answered all my questions here..and the one about the ECU has been answered elsewhere. The query re the door referred to the main cabin entrance door by the way, with my specific interest being as to the form of locking mechanism used. All is now clear however.
The questions were simplistic purely because I needed an overview of the type rather than any specific engineering details ( as such ).
Once again, thanks for your help.
