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BravoTwoVictor
5th Nov 2019, 11:02
Hi everyone, I'm currently looking at getting a share in an RF4d, but it doesn't have a transponder. I'm a fairly new power pilot but have about 75 hours in gliders, so have been flying without a transponder for a while but was wondering if powered pilots feel that not having a transponder restricts you in terms of Class D airspace transitions? I think part of the reason it doesn't have one is because of concerns on the amount of power required by a transponder, as the aircraft is battery powered.

If anyone had any ideas of the costs of purchasing and fitting a transponder on a LAA permit aircraft I'd be grateful, as well as any titbits about RF4s!

Dave Gittins
5th Nov 2019, 12:04
All depends where you are going to fly. If you are in the south east with loads of controlled airspace, LARS and listening squawks you definitely need one with Mode C …. If you are in the wilds of Wales with only a grass strip and no controlled airspace .. fill yer boots.

BravoTwoVictor
5th Nov 2019, 12:11
Oxfordshire based aircraft, so a fair bit around. This would be my first syndicate - I don't know how likely I'd be able to convince them to buy a transponder would be, especially as I can't really say how much it would cost.

ASRAAMTOO
5th Nov 2019, 15:05
Expect to pay about £1700 list price for a transponder plus fitting. You say its a permit aircraft so you may be able to do this yourselves. A modern transponder will not be too much of a drain on the battery although its possible your existing radio may be, unless its been replaced recemtly. If it hasn't then perhaps look for a 'package deal' from the same supplier/manufacturer at about £2800.

How receptive your syndicate partners are likely to be rather depends on the sort of flying they prefer to do.

Tay Cough
5th Nov 2019, 15:49
If it is a new installation, it must be Mode S.

BravoTwoVictor
5th Nov 2019, 21:22
Expect to pay about £1700 list price for a transponder plus fitting. You say its a permit aircraft so you may be able to do this yourselves. A modern transponder will not be too much of a drain on the battery although its possible your existing radio may be, unless its been replaced recemtly.

Radio is an 8.33 so I believe it's been replaced recently, though can't remember what brand. Do you know how much roughly it would cost? It's an LAA permit to fly.

Chuck Glider
6th Nov 2019, 05:29
IMO join the syndicate and see how you get on without a transponder. I rather expect you may enjoy the RF4 enough on its own to not worry much over the absence of SSR.

chevvron
6th Nov 2019, 14:33
All depends where you are going to fly. If you are in the south east with loads of controlled airspace, LARS and listening squawks you definitely need one with Mode C …. If you are in the wilds of Wales with only a grass strip and no controlled airspace .. fill yer boots.
It's nice to have but not essential if you're operating in Class G, you only really 'need' one to enter a TMZ or Class D airspace.
I fly microlights in class G with no transponder and used to own a powered glider similar to the Fournier which also didn't have one.

xrayalpha
6th Nov 2019, 21:01
You don't need a transponder for Class D - pop in and out of Glasgow's every week and Edinburgh's once a month.

mothminor
7th Nov 2019, 13:08
I fly in and out of Norwich zone without a transponder and sometimes even without a wireless ;)
Not flown an RF4 but the RF5 is lovely, do you now have to get one of those retract rating thingy`s? :*
Join the group and enjoy.

chevvron
8th Nov 2019, 00:19
You don't need a transponder for Class D - pop in and out of Glasgow's every week and Edinburgh's once a month.
I was referring to the south of England; to enter the Heathrow CTR you must have a transponder, but then again you must also have a dual ignition engine which I know the Fournier doesn't have.

hoodie
16th Nov 2019, 19:50
to enter the Heathrow CTR you ... must also have a dual ignition engine.
I've never heard of a rule that differentiates between GA ops in CAS and Class G based on the engine. What rule is that?

abgd
25th Nov 2019, 23:49
In any case, I thought the RF4 had a VW engine and they are normally converted to dual ignition for aviation use - edit, I see the RF4 was at least initially a CofA aircraft with a single mag and might still be?

I have a Turbulent which is a lovely aircraft to fly. It is just very different from anything I had flown previously, Pipers, Cessnas, similar beasts. At first I missed all the dials, levers and flashing lights in the bigger aircraft. Now I have grown to enjoy its simplicity. I am in the wilds of Wales and don't miss having a transponder at all. A few years back I used to hire a C152 from Blackbushe which didn't have one either. After a year or two of flying the Turbulent, when I had to sit in an IFR equipped 172 to revalidate it felt like sitting in a mini airliner. I was quite overwhelmed for the first few minutes. I often think that private pilots fall into two categories: retired airline pilots who like to fly cubs and off duty IT consultants who like to fly mini airliners. I started in the latter category (though not an IT consultant), but have found my tastes change.

There are two reasons to have a transponder. One is to help you. The other is to help other people.

The two problems I've had due to being transponderless were being made to fly complex patterns in a RMZ, and in the 152 having a radio failure. It would have been nice to be able to set 7600 on a transponder. The ATC in the RMZ sounded thoroughly stressed as she had one of the Airbus guppy thingies arriving not far away and I'm guessing I didn't give a good radar return as IIRC I had to do some climbs/descents as well. I found the experience quite interesting but I think it would be unfair on ATC if you were in a busy airspace and took up that much of their attention on a regular basis. There are doubtless some safety benefits to transponders in busy airspace. In Wales I very rarely see another aircraft on a flight, let alone come close to one. Flying spamcans round Scotland and Wales I also often found that my radio/transponder signal disappeared behind high terrain so I end up getting stressed making blind calls and worrying that people will be worrying about me disappearing from their screens, or hearing people tell me that I have disappeared from their screens and can't hear my reply. I have a satellite Personal Locator Beacon.

Personally if I were in your situation with some glider experience I could really see the appeal of a decent RF4. There's lots of fun to be had well clear of airspace. The questions I would be asking would be more to do with the other group members and maintenance. Who does it? Are they competent? My own experience is that there's often something to be fixed on an aircraft of this vintage and if you do need any new parts they will have to be fabricated which will be expensive if someone has to do it professionally.

jeepys
1st Dec 2019, 21:09
I don't think you are really looking at this the right way.

If all you are really concerned about is whether in not having one will restrict airspace in which you can fly then you will probably never buy one and perhaps aircraft ownership is not for you. The question should be "how much safer is it in having a transponder", to which the answer is considerable.
Our aircraft have TCAS which is a great safety tool. The number of aircraft I see on TCAS but cannot physically see is probably 20%. If I didn't have TCAS and they didn't have a transponder then quite a few contacts would go unnoticed. One day that might not happen. Mid air crashes are not impossible.

I know people will say a good scan is all you need and all TCAS does is draw you in to forget that, but I guarantee those people have never used it.

jmmoric
2nd Dec 2019, 11:31
After a few "where did he come from" situations, and one was really scary, I'd prefer to have as many instruments helping as possible, transponders, radars, whatnot...

Scanning still surprises you, no matter you're trying your best.

chevvron
2nd Dec 2019, 21:32
I've never heard of a rule that differentiates between GA ops in CAS and Class G based on the engine. What rule is that?
Well there certainly was a rule banning single ignition aircraft flying through the Heathrow CTR but maybe it was dropped when it became Class D airspace.
When it was the equivalent of Class A years ago, we had an OC Flying at Farnborough who was (and I believe still is) a bigwig in the BGA; knowing my experience of gliding we often had little chats about it and he admitted to me one day he'd flown an RF4 through the Heathrow CTR on a Special VFR clearance 'even though he shouldn't as it only had single ignition'.

FullWings
3rd Dec 2019, 06:06
I would echo the comments above about the utility of a transponder. IMO it does make a difference when getting clearances through CAS and, more importantly, it allows a significant set of other aircraft to become aware of your presence. ATC can also see you and advise conflicting traffic of your whereabouts, even if you are not talking to them.

Yes, it’s a significant investment but like a parachute, there are situations where it’s priceless.

Doesn’t cost much more to add something like PilotAware Rosetta and a tablet/phone running a nav app, which gives you nearly all the possible functionality.

Dave Gittins
3rd Dec 2019, 13:15
I am firmly in the school of if its available use it. So I have a transponder and get (whenever possible) a traffic service. If you don't want to talk to anybody, fine, squawk "listening" and at least the radar controller looking out for me can see you and the Gatwick Controllers won't be on the edge of their seats watching to see what you do next, because using that squawk implies you have an idea what you are up to and where you are.

Jan Olieslagers
3rd Dec 2019, 17:58
the radar controller looking out for me can see you

This makes for funny reading, even if it is not impossible to make a kind of sense out of the total posting. Just depends on who is "me" and who is "you" :)

Il Duce
3rd Dec 2019, 18:23
Makes sense: The radar controller looking out for me - the controller providing me with the Traffic Service; can see you - the conflicting traffic with its transponder switched on.

Fl1ingfrog
3rd Dec 2019, 21:10
This thread started with regard to an aircraft on battery power. Transponders are heavy power users and expensive, so impracticable in this case. No one has mentioned the NATS Eva project. The purpose was to identify the need of and specifications for low cost conspicuity: low cost and a low power demand was the overriding aim. FLARM, Trig, funkwerk and Pilotaware have produced an interesting array of units, utilising ADS-B and which do not demand a lot of power. They vary in price between £250 and £2,500.

Perhaps some pilots with a practical knowledge of this stuff may join in, otherwise I would suggest contacting the LAA who have a considerable and necessary expertise.

Jan Olieslagers
4th Dec 2019, 08:25
Technology has made quite some progress in recent years. On the one hand, transponders are much less power-hungry since the need for cavity magnetrons disappeared; on the other hand today's batteries store lots more energy per unit of weight. Many gliders carry both Flarm and a real transponder these days, powering both systems from batteries.

Jim59
4th Dec 2019, 09:45
This thread started with regard to an aircraft on battery power.
My understanding (from TRIG) is that their TT21 transponder when pretty busy consumes about 320 milliamps from a 12 volt battery so a dedicated 7A/h 12V battery when new could, theoretically, keep it going for about 20 hours. In practice batteries don't stay new for long and have lower capacity when cold so you may only get 10 hours per charge. Enough for a day's flying.

Dave Gittins
4th Dec 2019, 12:31
Must be the language barrier Jan :} at least Il Duce knew what I meant.

Fl1ingfrog
4th Dec 2019, 13:56
Transponders have a major limitation in that they are only a one way informer: Additional and separate equipment is required to read those transmissions from other aircraft. The main purpose of a transponder is to inform ATC. FLARM and the like inform all participants with two way/multi way information by transmitting and receiving at a low cost through its own unique systems but of late also through ADS-B therefore it can be read by all: ATC, fast jets, gliders and microlites including powered parachutes. This seems to me the best way to go particularly for vfr only aircraft who are the most likely to be in the mix.

Sam Rutherford
5th Dec 2019, 11:32
So, new one for me...

...flying low (about 2000') in Sudan last week, no radar for a few hundred miles - but the controller knew exactly where we were and our altitude.

ADS-B! The future is here...

Cheers, Sam.

Silvaire1
7th Dec 2019, 01:48
So, new one for me...

...flying low (about 2000') in Sudan last week, no radar for a few hundred miles - but the controller knew exactly where we were and our altitude.

ADS-B! The future is here...


The better future with ADS-B will be no controller required, self separation.